cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Previous Showing 31-33 of 33 results.

A124717 Number of base 24 circular n-digit numbers with adjacent digits differing by 1 or less.

Original entry on oeis.org

1, 24, 70, 162, 434, 1154, 3160, 8732, 24394, 68634, 194300, 552752, 1579004, 4526364, 13014190, 37515722, 108392314, 313803194, 910109980, 2643790592, 7691092024, 22403591624, 65337858370, 190759113662, 557493641284
Offset: 0

Views

Author

R. H. Hardin, Dec 28 2006

Keywords

Comments

[Empirical] a(base,n)=a(base-1,n)+A002426(n+1) for base>=1.int(n/2)+1
a(n) = T(n, 24) where T(n, k) = Sum_{j=1..k} (1+2*cos(j*Pi/(k+1)))^n. These are the number of smooth cyclic words of length n over the alphabet {1,2,..,24}. See theorem 3.3 in Knopfmacher and others, reference in A124696. - Peter Luschny, Aug 13 2012

A124718 Number of base 25 circular n-digit numbers with adjacent digits differing by 1 or less.

Original entry on oeis.org

1, 25, 73, 169, 453, 1205, 3301, 9125, 25501, 71773, 203253, 578405, 1652793, 4739305, 13630417, 39303329, 113588941, 328938125, 954262789, 2772787445, 8068471393, 23508942353, 68578993897, 200272341785, 585441977665
Offset: 0

Views

Author

R. H. Hardin, Dec 28 2006

Keywords

Comments

[Empirical] a(base,n)=a(base-1,n)+A002426(n+1) for base>=1.int(n/2)+1
a(n) = T(n, 25) where T(n, k) = Sum_{j=1..k} (1+2*cos(j*Pi/(k+1)))^n. These are the number of smooth cyclic words of length n over the alphabet {1,2,..,25}. See theorem 3.3 in Knopfmacher and others, reference in A124696. - Peter Luschny, Aug 13 2012

A342911 T(n, k) = Sum_{j=1..k} (1 + 2*cos(j*Pi/(k + 1)))^n for n > 0, T(0, 0) = 1. Triangle read by rows, T(n, k) for 0 <= k <= n.

Original entry on oeis.org

1, 0, 1, 0, 1, 4, 0, 1, 8, 15, 0, 1, 16, 35, 54, 0, 1, 32, 83, 134, 185, 0, 1, 64, 199, 340, 481, 622, 0, 1, 128, 479, 872, 1265, 1658, 2051, 0, 1, 256, 1155, 2254, 3361, 4468, 5575, 6682, 0, 1, 512, 2787, 5854, 8993, 12132, 15271, 18410, 21549
Offset: 0

Views

Author

Peter Luschny, Mar 28 2021

Keywords

Examples

			Triangle starts:
[0] 1
[1] 0, 1
[2] 0, 1, 4
[3] 0, 1, 8,   15
[4] 0, 1, 16,  35,   54
[5] 0, 1, 32,  83,   134,  185
[6] 0, 1, 64,  199,  340,  481,  622
[7] 0, 1, 128, 479,  872,  1265, 1658,  2051
[8] 0, 1, 256, 1155, 2254, 3361, 4468,  5575,  6682
[9] 0, 1, 512, 2787, 5854, 8993, 12132, 15271, 18410, 21549
		

Crossrefs

Programs

  • Maple
    T := (n, k) -> `if`(n=0, 1, add((1+2*cos(j*Pi/(k+1)))^n, j=1..k)):
    seq(seq(simplify(T(n, k)), k=0..n), n=0..8);
Previous Showing 31-33 of 33 results.