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.

Showing 1-3 of 3 results.

A176727 Denominator of a-sequence for Sheffer triangle A060081.

Original entry on oeis.org

1, 1, 3, 1, 15, 1, 21, 1, 45, 1, 33, 1, 1365, 1, 45, 1, 765, 1, 399, 1, 3465, 1, 1035, 1, 20475, 1, 189, 1, 435, 1, 7161, 1, 58905, 1, 315, 1, 959595, 1, 117, 1, 20295, 1, 148995, 1, 108675, 1, 14805, 1, 2436525, 1, 65637, 1, 78705, 1, 21945, 1, 24795, 1, 531, 1, 85180095, 1, 135135
Offset: 0

Views

Author

Wolfdieter Lang, Jul 14 2010

Keywords

Comments

The numerator sequence is A176726.
For a- and z-sequences for Sheffer triangles see the W. Lang link under A006232.

Examples

			Rationals A176726(n)/A176727(n): [1, 0, -2/3, 0, -32/15, 0, -704/21,0,...].

Links

Crossrefs

A176728/A176729 z-sequence for triangle A060081.

Programs

  • Mathematica
    max = 63; s = x/Log[Sqrt[(1+x)/(1-x)]] + O[x]^max; CoefficientList[s, x] * Range[0, max-1]! // Denominator (* Jean-François Alcover, Oct 04 2016 *)

Formula

E.g.f. for rational a-sequence A176726/A176727: x/log(sqrt((1+x)/(1- x))).

A176728 Numerator of z-sequence for Sheffer triangle A060081.

Original entry on oeis.org

1, 0, -1, 0, -17, 0, -1955, 0, -44089, 0, -4627969, 0, -10431967727, 0, -424734574531, 0, -187497600357613, 0, -263146180762981877, 0, -77335840394370605087, 0, -38414950218116664660463, 0, -95193934978797641162562791, 0, -1044549307308161782597280065, 0, -836232289988098415162220532417
Offset: 1

Views

Author

Wolfdieter Lang, Jul 14 2010

Keywords

Comments

The denominator sequence is A176729.
For a- and z-sequences for Sheffer triangles see the W. Lang link under A006232.

Examples

			Rationals A176728/A176729 with offset 0: [0,1/2,0,-1/4,0,-17/6,0,-1955/24,0,-44089/10,0,-4627969/12,... ].

Links

Crossrefs

A176726/A176727 a-sequence for triangle A060081.

Formula

E.g.f. for rationals A176728/A176729: (1-sqrt(1-x^2))/log(sqrt((1+x)/(1-x))). For n=0 one has a(0)=0.

A176729 Denominator of z-sequence for Sheffer triangle A060081.

Original entry on oeis.org

1, 2, 1, 4, 1, 6, 1, 24, 1, 10, 1, 12, 1, 210, 1, 48, 1, 90, 1, 420, 1, 330, 1, 360, 1, 1638, 1, 28, 1, 30, 1, 7392, 1, 510, 1, 36, 1, 51870, 1, 840, 1, 6930, 1, 13860, 1, 4830, 1, 1008, 1, 99450, 1, 5148, 1, 2970, 1, 3192, 1, 870, 1, 180, 1, 2792790, 1, 137280, 1, 1530, 1, 5796
Offset: 1

Views

Author

Wolfdieter Lang, Jul 14 2010

Keywords

Comments

The numerator sequence is A176728.

Examples

			Rationals A176728/A176729 with offset 0: [0, 1/2, 0, -1/4, 0, -17/6, 0, -1955/24, 0, -44089/10, 0, -4627969/12, ... ].

Links

Crossrefs

A176726/A176727 a-sequence for triangle A060081.

Formula

E.g.f. for rationals A176728/A176729: (1-sqrt(1-x^2))/log(sqrt((1+x)/(1-x))). For n=0 one has a(0)=1, hence A176728(0)/a(0)=0.
Showing 1-3 of 3 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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