Continued fraction convergents to sqrt(3)
creigh at o2online.de
creigh at o2online.de
Fri Nov 19 01:03:30 CET 2004
Hello,
(a(n)) and (b(n)), below, are two sequences I hope to be able to submit at
some time over the weekend:
Conjecture:
Define a(n) = A001835(n/2+1)_0, n even
= A003699((n+3)/2)_1, n odd
b(n) = A054485(n/2)_0, n even
= -A052530((n+1)/2)_0, n odd
Then | a(n) + b(n) | = 2*A002531(n+1)
A002531, Numerators of continued fraction convergents to sqrt(3).
A052530, A (nice) simple regular expression
A054485, A second order recursive sequence
A003699, Number of Hamilton cycles in C_4 X P_n
A001835 (nice)
Examples:
2*A002531(1) = 2 = 1 + 1 = | a(0) + b(0) | = A001835(1) + A054485(0)
// n = 0
2*A002531(2) = 4 = | 6 - 2 | = | a(1) + b(1) | = A003699(2) - A052530
(1) // n = 1
2*A002531(3) = 10 = 3 + 7 = | a(2) + b(2) | // n = 2
2*A002531(4) = 14 = |22 - 8| = | a(2) + b(2) | // n = 3
2*A002531(5) = 38 = 11 + 27 = | a(2) + b(2) | // n = 4
(It looks as if the absolute value signs will eventually get dropped.)
Concering FAMP's results leading to the above formula:
The generating floretion (see "results" below) is surprisingly simple (compare
this, for example, with the floretion given at the comment to http://www.
research.att.com/projects/OEIS?Anum=A001541
from yesterday). Also notice that "jes", "les", and "tes", below, do not
lead to any new formula in this case (and that additional sequences appear
which will also probably be of interest).
p.s. One of my favorite sequences found so far is the sequence
4achuseq[J]: -4, -3, -5, -5, -6, -6, -6, -5, -3, 1, 8, 20, 40, 73, 127,
215
which I found "buried" inside a batch of FAMP sequences (the sequence
Fibonacci numbers - 3 is in this same batch)
Sincerely,
Creighton
Results for the floretion:
***********************************************
+ 0.5'i + 0.5'k - 1i' + 0.5j' + 0.5k'
***********************************************
**************************** Static Symmetries
(squaring symmetries:)
vesseq: 1, -2, -5, 7, 19, -26, -71, 97, 265, -362, -989, 1351, 3691, -5042,
-13775, 18817, 51409,
tesseq: 0, -2, 0, 7, 0, -26, 0, 97, 0, -362, 0, 1351, 0, -5042, 0, 18817,
0, -70226, 0, 262087, 0,
lesseq: 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0
jesseq: 1, 0, -5, 0, 19, 0, -71, 0, 265, 0, -989, 0, 3691, 0, -13775,
0, 51409, 0, -191861, 0, 716035,
identity: ves = jes + les + tes
(Emmy's Three, subgroup symmetries:)
2em[I]seq: -1, -4, 1, 14, -3, -52, 11, 194, -41, -724, 153, 2702, -571, -10084,
2131, 37634
2em[I*]seq: 3, 0, -11, 0, 41, 0, -153, 0, 571, 0, -2131, 0, 7953, 0, -29681,
0
2em[J]seq: 1, -6, -3, 22, 11, -82, -41, 306, 153, -1142, -571, 4262, 2131, -15906,
-7953, 59362
// = (a(n))
2em[J*]seq: 1, 2, -7, -8, 27, 30, -101, -112, 377, 418, -1407, -1560,
5251, 5822, -19597, -21728
// = (b(n))
em[K]seq: 1, -2, -4, 7, 15, -26, -56, 97, 209, -362, -780, 1351, 2911, -5042,
-10864, 18817
em[K*]seq: 0, 0, -1, 0, 4, 0, -15, 0, 56, 0, -209, 0, 780, 0, -2911, 0
2famseq: 0, -5, 0, 18, 0, -67, 0, 250, 0, -933, 0, 3482, 0, -12995, 0,
48498
2fam*seq: 2, 1, -10, -4, 38, 15, -142, -56, 530, 209, -1978, -780, 7382,
2911, -27550, -10864
identities: em[I] + em[J] + em[K] = 2*fam + ves
em[I] + em[I*] = em[J] + em[J*] = em[K] + em[K*] = fam + fam* = ves
More information about the SeqFan
mailing list