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Posted

As a prisoner of visual art i need only give name rank and...

 

Eh it is with utmost reluctance i admit that...

 

By the way did you notice my reflections on circular work in telepathy?

 

What might the relation between our unconscious and the godspot be?

Posted

This is indeed a most fascinating topic. As a musician in the glorious 60's,

I did extensive research on the mathematics of music. Back then, there were no

"personal computers", "I phones" or even "calculators". We had to go an actual

building called a "library", math was done using our very own brains and

music was played by people who had talent.

 

Sadly, none of that is true today. Today, all we have are "instant mathematicians"

and "instant musicians" who would be utterly lost and helpless without their computers.

Today, with the aid of a computer, anyone can take some "on line" courses

and become a "musician". As a result, the world is now saturated with "auto tuned"

phonies such as "Justin Beaver", "Lady Goo Goo" and "Snoop Doggy Poop".

 

That said, the math involved in real music is a huge subject because

different cultures have different forms of music and make use of different scales.

The number of possible good sounding scales is actually quite unlimited.

 

Don.

Posted

As a prisoner of visual art i need only give name rank and...

 

Eh it is with utmost reluctance i admit that...

 

By the way did you notice my reflections on circular work in telepathy?

 

What might the relation between our unconscious and the godspot be?

 

at liberty of the visual arts i need only give art.

 

ahh it is with the utmost enthusiasm i hide that.

 

i have noticed your ring by the way. say "telephony" :phone:

 

what might...oh hell...i g0t nothin'. :lol:

 

ok. i have f12 powers for you to chordify -or not- as the case may be. :turtle: for crying out loud keep your arms inside the vehicle. :rotfl:

 

Posted

at liberty of the visual arts i need only give art.

 

ahh it is with the utmost enthusiasm i hide that.

 

i have noticed your ring by the way. say "telephony" :phone:

 

what might...oh hell...i g0t nothin'. :lol:

 

ok. i have f12 powers for you to chordify -or not- as the case may be. :turtle: for crying out loud keep your arms inside the vehicle. :rotfl:

 

Im taking a ... look at it (just before going to work) oh my! ...doesnt it resemble a piano ...say falling into pieces... Did you notice there has been a musician/mathematician dropping in to say hello?

 

Hi don :0001:

Posted

Im taking a ... look at it (just before going to work) oh my! ...doesnt it resemble a piano ...say falling into pieces... Did you notice there has been a musician/mathematician dropping in to say hello?

 

Hi don :0001:

 

:clue: yeah...i can see that if i squint. can you play it still? notice the power series n's jump around like the n's of the sequences you started with. f(7)=6 but f(12)=2. i did see don, yes. on the curmudgeonly side this week it seems. :rant: i dare say that i didn't make the piono fall apart in an instant nor did i use a computer. :painting:

 

next i'll smash up a well-tempered clavier, waht? :turtle: :hammer:

Posted

I think its best to proceed at a slow tempo, or rather concentrating on what has been and is going on.

1 f12=2?

2 temperisation... the pythagoreic comma ... as i said ... better taking it easy and check our foundation is solid! btw your knowledge of harmony theory is not non existent!!

3 Wouldnt it be nice if Don showed us some of his thoughts on the foundations and the beginning steps of Harmony Theory=HT1

4 I guess that HT1 is all that is done in order to introduce the Circles of fourths and fifths, when they are arrived at the study of tonality begins for real.The concept of "key" is introduced. At the moment i will identify it with the note used to produce the scale.

5 So when does a visiting Teacher of Harmony Theory shoes up giving us a lucid and thorough presentation of HT1? Whats done so far is no streamlined end product, though most pieces are here I think :)

 

PS What I said inspires me to add: The circles of fourths and fifths really are the same circle! the difference is direction

 

Fourths: BEADGCFA#D#G#C#F#

Fifths : F#C#G#D#A#FCGDAEB

 

Likewise A circle of thirds (the chord) is sixth backwards

 

Whats left is the circle of seconds (the scale) whis is seventh backwards...

 

Now then, why THREE circles? wondered sigurdV beginning this study.

 

PS we old swedes have difficulties with "b", we use "h" instead so if you see a "h" when there should be a "b" you know what mistake has been done.

 

6 My intention was using 5 numbers in order to point towards pentatonics ...But Why Bother About Formating... Now I remember what I wanted to say: I opened the thread "Is there an unconscious" inside the Phsycology forum and the first entry is approximately finished, but to continue I really would feel safer if I had something to respond to... like the beggar who asked for food and when refused, asked for a kettle of water so he could make soup with a nail.

Posted

dude!! you screwed up my post by editing the post i was quoting!!! i say again, make new posts, don't edit back onto old ones. it is not only a misdirection to readers, it can muck up other's posts.

 

so, i had my reply copied so let's go with that. :read:

 

I think its best to proceed at a slow tempo, or rather concentrating on what has been and is going on.

1 f12=2?

 

the last graph i gave is akin to your f(12) as it has 12 elements in the sequence; notes? you see @ top of graph 1 2 3 4 5 6 7 8 9 A B C. in using base notation >10 mathematicians/programmers begin using capital letters: A=10, B=11. C=12, etc..

 

anyway, my powers graph has only 2 steps and neither is the starting sequence. quite odd. not fallen apart; never together. recall this was not the case with my f(7) powers graph...the one you were imprisoned by/for/with.

 

2 temperisation... the pythagoreic comma ... as i said ... better taking it easy and check our foundation is solid! btw your knowledge of harmony theory is not non existent!!

 

i'm letting mr. jones' pages seep into my spongiform gray matter. :note: :daydreaming: i'm slow, but i do poor work. :lol:

 

3 Wouldnt it be nice if Don showed us some of his thoughts on the foundations and the beginning steps of Harmony Theory=HT1

 

ahh perchance to dream...

 

4 I guess that HT1 is all that is done in order to introduce the Circles of fourths and fifths, when they are arrived at the study of tonality begins for real.The concept of "key" is introduced. At the moment i will identify it with the note used to produce the scale.

5 So when does a visiting Teacher of Harmony Theory shoes up giving us a lucid and thorough presentation of HT1? Whats done so far is no streamlined end product, though most pieces are here I think :)

 

i'm still trying to grok the diagram. 9/8 waht??? isn't there some graphs...i know there are, that i should find that show all the harmonic vibrations in a plucked string? i'm on it like a turtle up a latter. :turtle:

Posted

ok

Ill try

but habits die hard!(but now I see a very good reason! thatll work)

see 6 in my previous entry, pleeeeeeeeeeeease enter something so I have a reason to proceed :)

Im curious as to where Don came from ...The music forum? Nah he is publishing in here.

Posted

HT 1 (=Harmony theory for Matematicians,Part 1): Lesson 1:Searching for the function Q:

 

True to my own advice im returning close to the origin (1=c)and claims there is a basical musical operation (taking thirds again and again, stop when next result is the beginning) defining a function f on x = a natural number, here follows the first twelve values:

 

x = 1 2 3 4 5 6 7 8 9 10 11 12

fx = 1 1 2 2 4 4 3 3 6 6 10 10

 

The function f is somewhat peculiar but is algorythmically defined.

 

Exercise 1 Prove that fn = fn+1 if n is odd!

 

Exercise 2 Define f as a non algoritmic function.

 

Exercise 3 Define f as a continous function. (=Q)

 

Exercise 4 Prove, or disprove that all values of the exponential function are values of Q.

 

Good Luck! Wishes sigurdV

Posted

HT 1 (=Harmony theory for Matematicians,Part 1): Lesson 1:Searching for the function Q:

 

True to my own advice im returning close to the origin (1=c)and claims there is a basical musical operation (taking thirds again and again, stop when next result is the beginning) defining a function f on x = a natural number, here follows the first twelve values:

 

x = 1 2 3 4 5 6 7 8 9 10 11 12

fx = 1 1 2 2 4 4 3 3 6 6 10 10

 

The function f is somewhat peculiar but is algorythmically defined.

 

Exercise 1 Prove that fn = fn+1 if n is odd!

 

Exercise 2 Define f as a non algoritmic function.

 

Exercise 3 Define f as a continous function. (=Q)

 

Exercise 4 Prove, or disprove that all values of the exponential function are values of Q.

 

Good Luck! Wishes sigurdV

 

:doh: all functions are algorithms. i don't think you're going to get the response(s) you want because you want a response in agreement with your pet idea(s). (0=1 0r is it 1=∞? non-standard though; oui/no) so, i think you're fn+1 business sounds like russel's principia mathematica. :shrug:

 

i read 6 & it is just another leash. :dogwalk:

 

don came from the non-figurate thread as best i recall. he's as up as you on being down on standards. :shrug:

 

here's the leash i referenced: :whip-new:

 

Vibrating String @ wiki

 

Vibration, standing waves in a string, The fundamental and the first 6 overtones which form a harmonic series.

 

Posted

A good visual aid! It helps me ordering my thoughts.

 

All functions algorithms? My nomenclature is deficient then. Id like to find a mathematical formula that can be used for determining the values of f. In a similar way as, say , the values of the exponential function is found by: y=xx

And...hmmm... You may be right about my pet ideas but i deny you can get them from what has been said in here.

 

The concept im honestly studying in here is: TONALITY

 

Info on it is appreciated. I claim that its first approximation is to notice that it is one of a triad achieved at by a basic operation on 1234567 provided the numbers are identified with the notes cdefgab.

 

also: f1=1 since you take the given and stop (since there is nothing left to jump over), f0=0 since theres no number to take,nor any number to jump over.If this has any bearing on my pet ideas is too early to say:)

 

so the first vibration gives 1=c, then 1/2=c, 1/3=g,1/4=c

it gets difficult... i should produce overtones on a string to check what notes i hear but i cant be certain of what divisions the 12 frets stand for...

 

Tuning down fourth string to c means fret 0 gives c

fret twelve gives pressed note c overtone c

fret seven gives g g

fret five f c

fret four e e

fret three d# g

fret two d d

fret one c# ?

 

Damn! I cant produce or hear the overtone at fret one:(

What I got = cdeg?

I believe the qustion mark stands for "a" since that would give me the c-pentatonic scale!

 

IF the missing notes f and b can be gotten as overtones they

should be found between fret 0 and fret one, but i hear no overtones there at all...(hm.. no good scientist am I? Iforgot checking som frets :fret ten gives A#A# -actually the overtone is between frets, ON fret 10 is D.)

 

Perhaps not so surprising: B and F is the border of the tonality C Major. (here i use the terms "key" and "tonality"

as equivalent... but tonality is a deeper concept than key.

 

Im not sure of what editing should be done of this entry,

i let it wait.

 

So ive done an empirical experiment...WOW... perhaps its relevant here to mention that a guitar ordinarily is tuned:

eadgbe counted from the thickest string.

 

It would be nice to communicate with a musician in here,so dear visitor why dont you get a guitar,learn how to tune it, and how to play it? If you dont have friends to help you out you can find i dont know how many amiable courses over the net. WHAT! You already did? You wonder how this so called composer teaches the guitar? I stand up to the challenge. Lets see what your fingers can do :)

 

First a word of warning: You will only if necessary be taught something that can be learnt elsewhere.

 

So (in the case the topic allows me to say the following):

1 Tune the d-string down a half step to c#

2 strum the guitar,again and again,try out rythms

3 If you did the tuning and retuning correct you listen to a rather pleasing chord... it is called A Major nine :)

Now you use the index finger to press down all strings at the same time at the first fret to produce the chord A# Major9. If this gives you problems then you truly are a beginner and should not worry, I assure you, just practise, and the A# will eventually sing out as nice as A did.

4 You are now at least in principle able to produce all Major nine chords!

fret 2 gives B

fret 3 gives C

fret 4 gives C#

fret 5 gives D

fret 6 gives D#

fret 7 gives E

fret 8 gives F

fret 9 gives F#

fret 10 gives G

fret 11 gives G#

fret 12 returns you to A!

 

The Major nine chord is (especially in blues and rock)an acceptable

substitute for the Major chord :)

If a real Major chord is needed just play the three thickest strings

Go ahead and practice, in #23 and in eventual entries not written yet, you will find some exercises intended for you.

Posted

One raises a question (Hi!), another attempts an answer (Whats new?), gets a question in return (Nothing in particular... etc etc.

 

Hi! Im Dr Fraud, and I think Id better introduce a lesser known fact about sigurd:

At a very early age he decided his Chamber Pot was explaining things to him:

 

Ma! Today it says "S"...

 

I am afraid that observation produced various dire (Watch out! End in sight! :censored: )

consequenses, among them his mother feeding him on oil

in order to suppress the ouija effect. :ghost:

 

On second thought (Get Thee Behind Me Dr) perhaps communication aint necessarily so simple as its Null Hypothesis (What do you think Mr Jones?) claims it to be.

 

I remember that working as a teacher worked best when I answered a Freely given question with answers carrying hidden statements provoking another question... If the strategy is properly carried out the roles of questioner and answerer actually gets reversed :)

 

Do you have an opinion in thiz matter?

 

Exercise : Explain what Socrates meant by claiming he knew nothing?

Posted

Hi there Don!

We here at the instituto of nothing will be very very happy to take on your case. Butt im wanted at the uNiVeRcItY as a participator in some mysterious experiment going on in there, (Cant imagine why they insisted me to digest nothing but coal since yesterday? ...Must be some really pressing matter i suppose) Anyway that simply means i cant make more than a supperficial analyzis of your text today.

1 This is indeed a most fascinating topic. As a musician in the glorious 60's,

I did extensive research on the mathematics of music. Back then, there were no

"personal computers", "I phones" or even "calculators". We had to go an actual

building called a "library", math was done using our very own brains and

music was played by people who had talent.

 

Sadly, none of that is true today. Today, all we have are "instant mathematicians"

and "instant musicians" who would be utterly lost and helpless without their computers.

Today, with the aid of a computer, anyone can take some "on line" courses

and become a "musician". As a result, the world is now saturated with "auto tuned"

phonies such as "Justin Beaver", "Lady Goo Goo" and "Snoop Doggy Poop".

 

That said, the math involved in real music is a huge subject because

different cultures have different forms of music and make use of different scales.

The number of possible good sounding scales is actually quite unlimited.

 

Don.

 

1 What do you think u mean by "This"?

Dr Smullian himself takes an interest in this question (which normally is used to prolong the treatment, in order to enlarge our wallets).

Posted

ok. try this from 2 terms through 13 terms. f=number of steps to repeat inclusive.

 

f=1

1 2

1 2

 

f=2

1 2 3

1 3 2

1 2 3

 

f=2

1 2 3 4

1 3 2 4

1 2 3 4

 

f=4

1 2 3 4 5

1 3 5 2 4

1 5 4 3 2

1 4 2 5 3

1 2 3 4 5

...

I can’t figure out how you’re generating these sequences, Turtle.

 

I get the sequences including most of yours by counting from 0 by (1 to B) modulo b – that is, with generator fuction

[math]a_{n+1} = ((a_n - 1 + i) \text{mod} m) + 1[/math]

Here are values for m = 1 to 16:

 1
1 2
1 1
1 2 3
1 3 2
1 1 1
1 2 3 4
1 3 1 3
1 4 3 2
1 1 1 1
1 2 3 4 5
1 3 5 2 4
1 4 2 5 3
1 5 4 3 2
1 1 1 1 1
1 2 3 4 5 6
1 3 5 1 3 5
1 4 1 4 1 4
1 5 3 1 5 3
1 6 5 4 3 2
1 1 1 1 1 1
1 2 3 4 5 6 7
1 3 5 7 2 4 6
1 4 7 3 6 2 5
1 5 2 6 3 7 4
1 6 4 2 7 5 3
1 7 6 5 4 3 2
1 1 1 1 1 1 1
1 2 3 4 5 6 7 8
1 3 5 7 1 3 5 7
1 4 7 2 5 8 3 6
1 5 1 5 1 5 1 5
1 6 3 8 5 2 7 4
1 7 5 3 1 7 5 3
1 8 7 6 5 4 3 2
1 1 1 1 1 1 1 1
1 2 3 4 5 6 7 8 9
1 3 5 7 9 2 4 6 8
1 4 7 1 4 7 1 4 7
1 5 9 4 8 3 7 2 6
1 6 2 7 3 8 4 9 5
1 7 4 1 7 4 1 7 4
1 8 6 4 2 9 7 5 3
1 9 8 7 6 5 4 3 2
1 1 1 1 1 1 1 1 1
 1  2  3  4  5  6  7  8  9 10
 1  3  5  7  9  1  3  5  7  9
 1  4  7 10  3  6  9  2  5  8
 1  5  9  3  7  1  5  9  3  7
 1  6  1  6  1  6  1  6  1  6
 1  7  3  9  5  1  7  3  9  5
 1  8  5  2  9  6  3 10  7  4
 1  9  7  5  3  1  9  7  5  3
 1 10  9  8  7  6  5  4  3  2
 1  1  1  1  1  1  1  1  1  1
 1  2  3  4  5  6  7  8  9 10 11
 1  3  5  7  9 11  2  4  6  8 10
 1  4  7 10  2  5  8 11  3  6  9
 1  5  9  2  6 10  3  7 11  4  8
 1  6 11  5 10  4  9  3  8  2  7
 1  7  2  8  3  9  4 10  5 11  6
 1  8  4 11  7  3 10  6  2  9  5
 1  9  6  3 11  8  5  2 10  7  4
 1 10  8  6  4  2 11  9  7  5  3
 1 11 10  9  8  7  6  5  4  3  2
 1  1  1  1  1  1  1  1  1  1  1
 1  2  3  4  5  6  7  8  9 10 11 12
 1  3  5  7  9 11  1  3  5  7  9 11
 1  4  7 10  1  4  7 10  1  4  7 10
 1  5  9  1  5  9  1  5  9  1  5  9
 1  6 11  4  9  2  7 12  5 10  3  8
 1  7  1  7  1  7  1  7  1  7  1  7
 1  8  3 10  5 12  7  2  9  4 11  6
 1  9  5  1  9  5  1  9  5  1  9  5
 1 10  7  4  1 10  7  4  1 10  7  4
 1 11  9  7  5  3  1 11  9  7  5  3
 1 12 11 10  9  8  7  6  5  4  3  2
 1  1  1  1  1  1  1  1  1  1  1  1
 1  2  3  4  5  6  7  8  9 10 11 12 13
 1  3  5  7  9 11 13  2  4  6  8 10 12
 1  4  7 10 13  3  6  9 12  2  5  8 11
 1  5  9 13  4  8 12  3  7 11  2  6 10
 1  6 11  3  8 13  5 10  2  7 12  4  9
 1  7 13  6 12  5 11  4 10  3  9  2  8
 1  8  2  9  3 10  4 11  5 12  6 13  7
 1  9  4 12  7  2 10  5 13  8  3 11  6
 1 10  6  2 11  7  3 12  8  4 13  9  5
 1 11  8  5  2 12  9  6  3 13 10  7  4
 1 12 10  8  6  4  2 13 11  9  7  5  3
 1 13 12 11 10  9  8  7  6  5  4  3  2
 1  1  1  1  1  1  1  1  1  1  1  1  1
 1  2  3  4  5  6  7  8  9 10 11 12 13 14
 1  3  5  7  9 11 13  1  3  5  7  9 11 13
 1  4  7 10 13  2  5  8 11 14  3  6  9 12
 1  5  9 13  3  7 11  1  5  9 13  3  7 11
 1  6 11  2  7 12  3  8 13  4  9 14  5 10
 1  7 13  5 11  3  9  1  7 13  5 11  3  9
 1  8  1  8  1  8  1  8  1  8  1  8  1  8
 1  9  3 11  5 13  7  1  9  3 11  5 13  7
 1 10  5 14  9  4 13  8  3 12  7  2 11  6
 1 11  7  3 13  9  5  1 11  7  3 13  9  5
 1 12  9  6  3 14 11  8  5  2 13 10  7  4
 1 13 11  9  7  5  3  1 13 11  9  7  5  3
 1 14 13 12 11 10  9  8  7  6  5  4  3  2
 1  1  1  1  1  1  1  1  1  1  1  1  1  1
 1  2  3  4  5  6  7  8  9 10 11 12 13 14 15
 1  3  5  7  9 11 13 15  2  4  6  8 10 12 14
 1  4  7 10 13  1  4  7 10 13  1  4  7 10 13
 1  5  9 13  2  6 10 14  3  7 11 15  4  8 12
 1  6 11  1  6 11  1  6 11  1  6 11  1  6 11
 1  7 13  4 10  1  7 13  4 10  1  7 13  4 10
 1  8 15  7 14  6 13  5 12  4 11  3 10  2  9
 1  9  2 10  3 11  4 12  5 13  6 14  7 15  8
 1 10  4 13  7  1 10  4 13  7  1 10  4 13  7
 1 11  6  1 11  6  1 11  6  1 11  6  1 11  6
 1 12  8  4 15 11  7  3 14 10  6  2 13  9  5
 1 13 10  7  4  1 13 10  7  4  1 13 10  7  4
 1 14 12 10  8  6  4  2 15 13 11  9  7  5  3
 1 15 14 13 12 11 10  9  8  7  6  5  4  3  2
 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1
 1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16
 1  3  5  7  9 11 13 15  1  3  5  7  9 11 13 15
 1  4  7 10 13 16  3  6  9 12 15  2  5  8 11 14
 1  5  9 13  1  5  9 13  1  5  9 13  1  5  9 13
 1  6 11 16  5 10 15  4  9 14  3  8 13  2  7 12
 1  7 13  3  9 15  5 11  1  7 13  3  9 15  5 11
 1  8 15  6 13  4 11  2  9 16  7 14  5 12  3 10
 1  9  1  9  1  9  1  9  1  9  1  9  1  9  1  9
 1 10  3 12  5 14  7 16  9  2 11  4 13  6 15  8
 1 11  5 15  9  3 13  7  1 11  5 15  9  3 13  7
 1 12  7  2 13  8  3 14  9  4 15 10  5 16 11  6
 1 13  9  5  1 13  9  5  1 13  9  5  1 13  9  5
 1 14 11  8  5  2 15 12  9  6  3 16 13 10  7  4
 1 15 13 11  9  7  5  3  1 15 13 11  9  7  5  3
 1 16 15 14 13 12 11 10  9  8  7  6  5  4  3  2
 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1

But mine matches your for some cases, such as m=11, but not others, such as m=6:

Yours (f=4):

1 2 3 4 5 6

1 3 5 2 4 6

1 5 4 3 2 6

1 4 2 5 3 6

1 2 3 4 5 6

Mine (m=6):

1 2 3 4 5 6

1 3 5 1 3 5

1 4 1 4 1 4

1 5 3 1 5 3

1 6 5 4 3 2

1 1 1 1 1 1

 

What’s you algorithm?

Posted

I can’t figure out how you’re generating these sequences, Turtle.

 

...

But mine matches your for some cases, such as m=11, but not others, such as m=6:

Yours (f=4):

1 2 3 4 5 6

1 3 5 2 4 6

1 5 4 3 2 6

1 4 2 5 3 6

1 2 3 4 5 6

Mine (m=6):

1 2 3 4 5 6

1 3 5 1 3 5

1 4 1 4 1 4

1 5 3 1 5 3

1 6 5 4 3 2

1 1 1 1 1 1

 

What’s you algorithm?

 

beginning with the sequence:

1 2 3 4 5 6

list the first number in the beginning sequence to get the first number in the new sequence:

1

skip the second number in the beginning sequence and list the third number of the beginning sequence as second in the new sequence:

1 3

skip the fourth number in the beginning sequence and list the fifth number of the beginning sequence as the third number in the new sequence:

1 3 5

skip the sixth number in the beginning sequence and return back to the first skipped number in the beginning sequence and list the first skipped number in the beginning sequence as the fourth number in the new sequence:

1 3 5 2

skip the third number in the beginning sequence and list the fourth number from the beginning sequence as the fifth number in the new sequence:

1 3 5 2 4

skip the fifth number in the beginning sequence and list the sixth number from the beginning sequence as the sixth number in the new sequence:

1 3 5 2 4 6

 

the new sequence becomes the beginning sequence. rinse & repeat until the series returns to the original sequence. count the number of steps/sequences, not including the repeat. doing this i got:

 

f(6)=4

1 2 3 4 5 6

1 3 5 2 4 6

1 5 4 3 2 6

1 4 2 5 3 6

1 2 3 4 5 6

 

 

:turtle: i did this by hand/eye so i certainly may have made mistakes. i caught a few, but they became obvious rather quickly as they jossle the later patterns.

Posted

beginning with the sequence:

1 2 3 4 5 6 ...

Thanks. I seem of late to be some combination of stupid and lazy, or ... yeah, efficient, that’s it. Much more efficient having you tell me the algorithm rather than trying to puzzling it out myself. :)

 

Now my trusty computer can crank these sequences out – here are the first 11 groups of them:

 1
f(1)=1
1 2
f(2)=1
1 3 2
1 2 3
f(3)=2
1 3 2 4
1 2 3 4
f(4)=2
1 3 5 2 4
1 5 4 3 2
1 4 2 5 3
1 2 3 4 5
f(5)=4
1 3 5 2 4 6
1 5 4 3 2 6
1 4 2 5 3 6
1 2 3 4 5 6
f(6)=4
1 3 5 7 2 4 6
1 5 2 6 3 7 4
1 2 3 4 5 6 7
f(7)=3
1 3 5 7 2 4 6 8
1 5 2 6 3 7 4 8
1 2 3 4 5 6 7 8
f(8)=3
1 3 5 7 9 2 4 6 8
1 5 9 4 8 3 7 2 6
1 9 8 7 6 5 4 3 2
1 8 6 4 2 9 7 5 3
1 6 2 7 3 8 4 9 5
1 2 3 4 5 6 7 8 9
f(9)=6
1 3 5 7 9 2 4 6 8 10
1 5 9 4 8 3 7 2 6 10
1 9 8 7 6 5 4 3 2 10
1 8 6 4 2 9 7 5 3 10
1 6 2 7 3 8 4 9 5 10
1 2 3 4 5 6 7 8 9 10
f(10)=6
1 3 5 7 9 11 2 4 6 8 10
1 5 9 2 6 10 3 7 11 4 8
1 9 6 3 11 8 5 2 10 7 4
1 6 11 5 10 4 9 3 8 2 7
1 11 10 9 8 7 6 5 4 3 2
1 10 8 6 4 2 11 9 7 5 3
1 8 4 11 7 3 10 6 2 9 5
1 4 7 10 2 5 8 11 3 6 9
1 7 2 8 3 9 4 10 5 11 6
1 2 3 4 5 6 7 8 9 10 11
f(11)=10

Here are the values of f() for the first 1000, ten to a row for viewing ease:

  n: f(n)
 1:   1   1   2   2   4   4   3   3   6   6
11:  10  10  12  12   4   4   8   8  18  18
21:   6   6  11  11  20  20  18  18  28  28
31:   5   5  10  10  12  12  36  36  12  12
41:  20  20  14  14  12  12  23  23  21  21
51:   8   8  52  52  20  20  18  18  58  58
61:  60  60   6   6  12  12  66  66  22  22
71:  35  35   9   9  20  20  30  30  39  39
81:  54  54  82  82   8   8  28  28  11  11
91:  12  12  10  10  36  36  48  48  30  30
101: 100 100  51  51  12  12 106 106  36  36
111:  36  36  28  28  44  44  12  12  24  24
121: 110 110  20  20 100 100   7   7  14  14
131: 130 130  18  18  36  36  68  68 138 138
141:  46  46  60  60  28  28  42  42 148 148
151:  15  15  24  24  20  20  52  52  52  52
161:  33  33 162 162  20  20  83  83 156 156
171:  18  18 172 172  60  60  58  58 178 178
181: 180 180  60  60  36  36  40  40  18  18
191:  95  95  96  96  12  12 196 196  99  99
201:  66  66  84  84  20  20  66  66  90  90
211: 210 210  70  70  28  28  15  15  18  18
221:  24  24  37  37  60  60 226 226  76  76
231:  30  30  29  29  92  92  78  78 119 119
241:  24  24 162 162  84  84  36  36  82  82
251:  50  50 110 110   8   8  16  16  36  36
261:  84  84 131 131  52  52  22  22 268 268
271: 135 135  12  12  20  20  92  92  30  30
281:  70  70  94  94  36  36  60  60 136 136
291:  48  48 292 292 116 116  90  90 132 132
301:  42  42 100 100  60  60 102 102 102 102
311: 155 155 156 156  12  12 316 316 140 140
321: 106 106  72  72  60  60  36  36  69  69
331:  30  30  36  36 132 132  21  21  28  28
341:  10  10 147 147  44  44 346 346 348 348
351:  36  36  88  88 140 140  24  24 179 179
361: 342 342 110 110  36  36 183 183  60  60
371: 156 156 372 372 100 100  84  84 378 378
381:  14  14 191 191  60  60  42  42 388 388
391:  88  88 130 130 156 156  44  44  18  18
401: 200 200  60  60 108 108 180 180 204 204
411:  68  68 174 174 164 164 138 138 418 418
421: 420 420 138 138  40  40  60  60  60  60
431:  43  43  72  72  28  28 198 198  73  73
441:  42  42 442 442  44  44 148 148 224 224
451:  20  20  30  30  12  12  76  76  72  72
461: 460 460 231 231  20  20 466 466  66  66
471:  52  52  70  70 180 180 156 156 239 239
481:  36  36  66  66  48  48 243 243 162 162
491: 490 490  56  56  60  60 105 105 166 166
501: 166 166 251 251 100 100 156 156 508 508
511:   9   9  18  18 204 204 230 230 172 172
521: 260 260 522 522  60  60  40  40 253 253
531: 174 174  60  60 212 212 178 178 210 210
541: 540 540 180 180  36  36 546 546  60  60
551: 252 252  39  39  36  36 556 556  84  84
561:  40  40 562 562  28  28  54  54 284 284
571: 114 114 190 190 220 220 144 144  96  96
581: 246 246 260 260  12  12 586 586  90  90
591: 196 196 148 148  24  24 198 198 299 299
601:  25  25  66  66 220 220 303 303  84  84
611: 276 276 612 612  20  20 154 154 618 618
621: 198 198  33  33 500 500  90  90  72  72
631:  45  45 210 210  28  28  84  84 210 210
641:  64  64 214 214  28  28 323 323 290 290
651:  30  30 652 652 260 260  18  18 658 658
661: 660 660  24  24  36  36 308 308  74  74
671:  60  60  48  48 180 180 676 676  48  48
681: 226 226  22  22  68  68  76  76 156 156
691: 230 230  30  30 276 276  40  40  58  58
701: 700 700  36  36  92  92 300 300 708 708
711:  78  78  55  55  60  60 238 238 359 359
721:  51  51  24  24 140 140 121 121 486 486
731:  56  56 244 244  84  84 330 330 246 246
741:  36  36 371 371 148 148 246 246 318 318
751: 375 375  50  50  60  60 756 756 110 110
761: 380 380  36  36  24  24 348 348 384 384
771:  16  16 772 772  20  20  36  36 180 180
781:  70  70 252 252  52  52 786 786 262 262
791:  84  84  60  60  52  52 796 796 184 184
801:  66  66  90  90 132 132 268 268 404 404
811: 270 270 270 270 324 324 126 126  12  12
821: 820 820 411 411  20  20 826 826 828 828
831:  92  92 168 168 332 332  90  90 419 419
841: 812 812  70  70 156 156 330 330  94  94
851: 396 396 852 852  36  36 428 428 858 858
861:  60  60 431 431 172 172 136 136 390 390
871: 132 132  48  48 300 300 876 876 292 292
881:  55  55 882 882 116 116 443 443  21  21
891: 270 270 414 414 356 356 132 132 140 140
901: 104 104  42  42 180 180 906 906 300 300
911:  91  91 410 410  60  60 390 390 153 153
921: 102 102 420 420 180 180 102 102 464 464
931: 126 126 310 310  40  40 117 117 156 156
941: 940 940 220 220  36  36 946 946  36  36
951: 316 316  68  68 380 380 140 140 204 204
961: 155 155 318 318  96  96 483 483  72  72
971: 194 194 138 138  60  60 488 488 110 110
981:  36  36 491 491 196 196 138 138 154 154
991: 495 495  30  30 396 396 332 332  36  36

I find interesting that, periodically, f(n)=n-1, for example, for the following values of n:

2 3 5 11 13 19 29 37 53 59 61 67 83 101 107 131 139 149 163 173 179 181 197 211
227 269 293 317 347 349 373 379 389 419 421 443 461 467 491 509 523 541 547 557
563 587 613 619 653 659 661 677 701 709 757 773 787 797 821 827 829 853 859 877
883 907 941 947 1019

For these 1st 69 cases of f(n)=n-1, n is always prime, but follows no pattern of skipping primes that I can intuit:

1:2 2:3 3:5    4:7 
5:11 6:13    7:17 
8:19    9:23 
10:29    11:31 
12:37    13:41 14:43 15:47 
16:53 17:59 18:61 19:67    20:71 21:73 22:79 
23:83    24:89 25:97 
26:101    27:103 
28:107    29:109 30:113 31:127 
32:131    33:137 
34:139 35:149    36:151 37:157 
38:163    39:167 
40:173 41:179 42:181    43:191 44:193 
45:197     46:199 
47:211    48:223 
49:227    50:229 51:233 52:239 53:241 54:251 55:257 56:263 
57:269    58:271 59:277 60:281 61:283 
62:293    63:307 64:311 65:313 
66:317    67:331 68:337 
69:347 70:349    71:353 72:359 73:367 
74:373 75:379    76:383 
77:389    78:397 79:401 80:409 
81:419 82:421    83:431 84:433 85:439 
86:443    87:449 88:457 
89:461    90:463 
91:467    92:479 93:487 
94:491    95:499 96:503 
97:509    98:521 
99:523 100:541 101:547 102:557 103:563    104:569 105:571 106:577 
107:587    108:593 109:599 110:601 111:607 
112:613    113:617 
114:619    115:631 116:641 117:643 118:647 
119:653 120:659 121:661    122:673 
123:677    124:683 125:691 
126:701 127:709    128:719 129:727 130:733 131:739 132:743 133:751 
134:757    135:761 136:769 
137:773 138:787 139:797    140:809 141:811 
142:821    143:823 
144:827 145:829    146:839 
147:853    148:857 
149:859    150:863 
151:877    152:881 
153:883    154:887 
155:907    156:911 157:919 158:929 159:937 
160:941 161:947    162:953 163:967 164:971 165:977 166:983 167:991 168:997 169:1009 170:1013 
171:1019

I’m pretty badly off the topic of the mathematics of sound and music, but can’t resist a discrete math indulgence. ;)

Posted

Thanks. I seem of late to be some combination of stupid and lazy, or ... yeah, efficient, that’s it. Much more efficient having you tell me the algorithm rather than trying to puzzling it out myself. :)

ahh the foe is on the other shoot. :lol: i had to ask too. :crazy:

 

Now my trusty computer can crank these sequences out – here are the first 11 groups of them:
 1
f(1)=1
1 2
f(2)=1
1 3 2
1 2 3
f(3)=2
1 3 2 4
1 2 3 4
f(4)=2
1 3 5 2 4
1 5 4 3 2
1 4 2 5 3
1 2 3 4 5
f(5)=4
1 3 5 2 4 6
1 5 4 3 2 6
1 4 2 5 3 6
1 2 3 4 5 6
f(6)=4
1 3 5 7 2 4 6
1 5 2 6 3 7 4
1 2 3 4 5 6 7
f(7)=3
1 3 5 7 2 4 6 8
1 5 2 6 3 7 4 8
1 2 3 4 5 6 7 8
f(8)=3
1 3 5 7 9 2 4 6 8
1 5 9 4 8 3 7 2 6
1 9 8 7 6 5 4 3 2
1 8 6 4 2 9 7 5 3
1 6 2 7 3 8 4 9 5
1 2 3 4 5 6 7 8 9
...

Here are the values of f() for the first 1000, ten to a row for viewing ease:

  n: f(n)
 1:   1   1   2   2   4   4   3   3   6   6
11:  10  10  12  12   4   4   8   8  18  18
21:   6   6  11  11  20  20  18  18  28  28
31:   5   5  10  10  12  12  36  36  12  12
41:  20  20  14  14  12  12  23  23  21  21
...

I find interesting that, periodically, f(n)=n-1, for example, for the following values of n:

2 3 5 11 13 19 29 37 53 59 61 67 83 101 107 131 139 149 163 173 179 181 197 211 227 269 293 317 347 349 373 379 389 419 421 443 461 467 491 509 523 541 547 557 563 587 613 619 653 659 661 677 701 709 757 773 787 797 821 827 829 853 859 877 883 907 941 947 1019

 

at first i thought you had a repeating error in there, but now i see that i find it interesting that for all f(n) when n is odd, f(n)=f(n+1).

 

For these 1st 69 cases of f(n)=n-1, n is always prime, but follows no pattern of skipping primes that I can intuit:
1:2 2:3 3:5    4:7 
5:11 6:13    7:17 
8:19    9:23 
10:29    11:31 
12:37    13:41 14:43 15:47 
16:53 17:59 18:61 19:67    20:71 21:73 22:79 
23:83    24:89 25:97 
...

I’m pretty badly off the topic of the mathematics of sound and music, but can’t resist a discrete math indulgence. ;)

 

nothing jumps right out at me either. :clue: will go off and stare some more.

 

as to music, sigurd originally set f(7) as an octave and equated the steps and the number of steps, f(7)=3, to the musical qualities "scale", "chord", and "tonality". then, i think, he was asking if other sequences/length-of-scales have matching or otherwise musically interesting steps and/or numbers of steps. i can't quite tell what the conclusion is/was. :reallyconfused:

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