"Convergents to golden ratio" sequnces, "tribonacci" sequences, and the "helious sequnce".

creigh at o2online.de creigh at o2online.de
Fri Dec 24 17:16:50 CET 2004


Dear Seqfans, 

It seems to me the sequences given, below, dealing with "convergents to golden 
ratio" and (another set of sequences concerning) "tribonacci numbers" should 
be of interest. I have also included a bit about the "helious sequence" 
further down the page. I will submit a few of these over the next  few days. 
(and many greetings!)

Results for the floretion:  I*H
 

****************************************************************************************************
 
 + .5'k + .5k' - .5'jj' + 'ij' + .5'ik' + 'ji' + .5'jk' + .5'ki' + .5'kj' + 
.5e 
 

****************************************************************************************************

 
I =  + 'i + i' + 'ij' + 'ji'
H =  + .5'j + .5j' + .5'ji' + .5'kj' + .5e

 
 Invariant to swap operator: yes, as it commutes with the floretion 'ii' + 
'jj' + 'kk' - 1
 
Note: Sequences, below, refer to I*H 

 
1vesseq: 5, 9, 38, 112, 376, 1200, 3904, 12608, 40832, 132096, 427520, 1383424, 4476928, 
14487552, 46882816, 15171584, 490962944, 1588789248, 5141430272, 16638017536, 
5384175616
//unlisted
 
 2tesseq: 1, 6, 16, 56, 176, 576, 1856, 6016, 19456, 62976, 203776,  
 http://www.research.att.com/projects/OEIS?Anum=A084057
Inverse binomial transform of A001077. Binomial transform of
expansion of cosh(sqrt(5)x) (1,0,5,0,25,...).

 2lesseq: 7, 14, 56, 168, 560, 1792, 5824, 18816, 60928, 197120, 
 Convergents to golden ratio (1+sqrt(5))/2.
 G.f.: 1/(1-2*x-4*x^2).
http://www.research.att.com/projects/OEIS?Anum=A063727


 1jesseq: 1, -1, 2, 0, 8, 16, 64, 192, 640, 2048, 6656, 21504, 69632, 
 http://www.research.att.com/projects/OEIS?Anum=A087205
Inverse binomial transform of A087204

 
 1em[I]seq: 1, 2, 8, 24, 80, 256, 832, 2688, 8704, 28160, 91136, 
 Convergents to golden ratio (1+sqrt(5))/2

 1em[I*]seq: 4, 7, 30, 88, 296, 944, 3072, 9920, 32128, 103936, 336384, 1088512, 
3522560, 11399168, 36888576, 119373824, 386301952, 12500992, 4045406208, 
13091209216, 
 // unlisted

 1em[J]seq: 1, 3, 10, 32, 104, 336, 1088, 3520, 11392, 36864, 
Ratio of successive terms approaches sqrt(5) + 1.
http://www.research.att.com/projects/OEIS?Anum=A063782

 1em[J*]seq: 4, 6, 28, 80, 272, 864, 2816, 9088, 29440, 95232, 308224, 997376, 
3227648, 104448, 33800192, 109379584, 353959936, 1145438208, 370671616, 
11995185152, 
 //unlisted 

 1em[K]seq: 3, 4, 20, 56, 192, 608, 1984, 6400, 20736, 67072, 217088, 702464, 
2273280, 7356416, 23805952, 77037568, 249298944, 80674816, 2610692096, 8448376832, 
//unlisted

 1em[K*]seq: 2, 5, 18, 56, 184, 592, 1920, 6208, 20096, 65024, 210432, 680960, 
2203648, 7131136, 23076864, 74678272, 241664, 782041088, 2530738176, 8189640704, 
26502234112, 
 
 1famseq: 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 
0, 0, 
 1fam*seq: 5, 9, 38, 112, 376, 1200, 3904, 12608, 40832, 132096, 427520, 
1383424, 4476928, 14487552, 46882816, 15171584, 490962944, 1588789248, 5141430272, 
16638017536, 

identities: 
em[I] + em[J] + em[K] = 2fam + ves  ;
em[I] + em[I*] = em[J] + em[J*] = em[K] + em[K*] = fam + fam* = ves  ;
jes + les + tes = ves


Note: Sequences, below, refer to H*I 

 
1vesseq: -1, 1, -2, 0, -8, -16, -64, -192, -640, -2048, -6656, -21504, -
see jesseq(I*H), above
 
2tesseq: 1, 6, 16, 56, 176, 576, 1856, 6016, 19456, 62976, 203776, 659456, 2134016, 
6905856, 22347776, 72318976, 234029056, 757334016, 2450784256, 7930904576, 
25664946176, 83053510656
 
2lesseq: 1, 2, 8, 24, 80, 256, 832, 2688, 8704, 28160, 91136, 294912, 
see em[I]seq(I*H), above;   

 1jesseq: -2, -3, -14, -40, -136, -432, -1408, -4544, -14720, -47616, -154112, 
-498688, -1613824, -5222400, -16900096, -54689792, -176979968, -572719104, 
-185335808, -5997592576, -19408617472, -62807605248
 //unlisted 

 2jesleftseq: -3, -5, -22, -64, -216, -688, -2240, -7232, -23424, -75776, -245248, 
-793600, -2568192, -8310784, -26894336, -87031808, -28164096, -911409152, 
-2949382144,  // unlisted 

 2jesrightseq: -1, -1, -6, -16, -56, -176, -576, -1856, -6016, -19456, -
// see tes (this sequence has an additional term) 

 1em[I]seq: -1, 2, 0, 8, 16, 64, 192, 640, 2048, 6656, 21504, 69632,  
 1em[I*]seq: 0, -1, -2, -8, -24, -80, -256, -832, -2688, -8704, -28160, 
-91136, -294912, -954368, 


Concerning tribonacci numbers: 

Results for the floretion:  E*N
 

****************************************************************************************************

 
 - .5'i - .5'j - .5'ii' + .5'jj' - .5'kk' - .5'ij' - .5'ik' + .5'ki' 
 

****************************************************************************************************

  
1vesseq: -2, -1, -2, -5, -8, -15, -28, -51, -94, -173, -318, -585, -1076, -1979, 
-3640, -6695, -12314, 

-22649, -41658, -76621, -140928, -259207, -476756, -876891, -1612854, -2966501, 
-5456246,  
 // unlisted 

 2tesseq: 0, 2, 3, 6, 10, 20, 35, 66, 120, 222, 407, 750, 1378, 2536, 4663, 
8578, 15776, 29018, 53371, 98166, 180554, 332092, 610811, 1123458, 2066360, 
3800630, 6990447, 12857438,  
 // unlisted

 2lesseq: -2, -2, -3, -8, -12, -24, -43, -80, -146, -270, -495, -912, -1676, 
-3084, -5671, -10432, -19186, -35290, -64907, -119384, -219580, -403872, 
-742835, -1366288, -2512994, -4622118,  
 // unlisted 

 1jesseq: -1, -1, -2, -4, -7, -13, -24, -44, -81, -149, -274, -504, -927, -1705, 
-3136, -5768, -10609, -19513, -35890, -66012, -121415, -223317, -410744, 
-755476, -1389537, -2555757, -4700770,  
 http://www.research.att.com/projects/OEIS?Anum=A000073
tribonacci numbers 


 2jesleftseq: -2, 0, -3, -4, -8, -14, -27, -48, -90, -164, -303, -556, -1024, -1882, 
-3463, -6368, -11714, -21544, -39627, -72884, -134056, -246566, -453507, 
-834128, -1534202, -2821836,  
 // unlisted 

 2jesrightseq: 0, -2, -1, -4, -6, -12, -21, -40, -72, -134, -245, -452, -830, 
-1528, -2809, -5168, -9504, -17482, -32153, -59140, -108774, -200068, -367981, 
-676824, -1244872, -2289678,  

identities:
jes + les + tes = ves
jesleft + jesright = jes

Note: the sequences "jesleft", "jesright" and "jes" are referred to as the 
"jes series", in the (top) comment to 
http://www.research.att.com/projects/OEIS?Anum=A001109
as well as in 
http://www.research.att.com/projects/OEIS?Anum=A005251

Finally, 
Regarding the "helious" sequence
http://www.research.att.com/projects/OEIS?Anum=A097357

Yesterday, I put a few observations as well as the first 3000 terms of the 
sequence into the file "heliouscheck.txt" at
http://www.crowdog.de/15301.html

Notice the strings "3, 6, 3, 9, 9", "5, 10, 5, 15, 15", and "11, 22, 11" appear 
to repeat an infinite number of times in the sequence. This led me to give 
some thought to the term preceding any such string. I noticed the following: 

Twice the term immediately preceding "3,6,3,9,9" subtracted by the term immediately 

preceding the next occurance of  "3,6,3,9,9" in the sequence gives:
 
2*11 - 22 = 0
2*22 - 43 = 1
2*43 - 86 = 0
2*86 - 171 =  1
2*171 - 342 = 0 
2*342 - 683 = 1
2*683 - 1366 = 0
2*1366 - 2731 = 1

Twice the term immediately preceding "5, 10, 5, 15, 15" subtracted by the 
term immediately 

preceding the next occurance of  "5, 10, 5, 15, 15" in the sequence gives:

31*2 - 64 = - 2
64*2 - 127 = 1
127*2 - 256 = -2
2*256 - 511 = 1
511*2 - 1024 = -2

// same as above with "11, 22, 11"

2*28 - 53 = 3
2*53 - 108 = -2
2*108 - 213 = 3
2*213 - 428 = -2
428*2 - 853 = 3

Would anyone be interested in making an animation out of rings in the picture 
given at the link? If, in addition, the user could set the number and initial 
placement of these rings (for ex., using a mouse) then that user will have 
effictively created his/her own sequence as it depends on these values. 

Sincerely, 
Creighton 






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