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.

A085350 Binomial transform of poly-Bernoulli numbers A027649.

Original entry on oeis.org

1, 5, 23, 101, 431, 1805, 7463, 30581, 124511, 504605, 2038103, 8211461, 33022991, 132623405, 532087943, 2133134741, 8546887871, 34230598205, 137051532983, 548593552421, 2195536471151, 8785632669005, 35152991029223
Offset: 0

Views

Author

Paul Barry, Jun 24 2003

Keywords

Comments

Binomial transform is A085351.
a(n) mod 10 = period 4:repeat 1,5,3,1 = A132400. - Paul Curtz, Nov 13 2009

Crossrefs

a(n-1) = A080643(n)/2 = A081674(n+1) - A081674(n).
Cf. A000244 (3^n).

Programs

  • Magma
    [2*4^n-3^n: n in [0..30]]; // Vincenzo Librandi, Aug 13 2011
  • Mathematica
    LinearRecurrence[{4,9,-36},{1,5,23},30] (* Harvey P. Dale, Nov 30 2011 *)
    LinearRecurrence[{7, -12},{1, 5},23] (* Ray Chandler, Aug 03 2015 *)

Formula

G.f.: (1-2x)/((1-3x)(1-4x)).
E.g.f.: 2exp(4x) - exp(3x).
a(n) = 2*4^n-3^n.
From Paul Curtz, Nov 13 2009: (Start)
a(n) = 4*a(n-1) + 9*a(n-2) - 36*a(n-3);
a(n) = 4*a(n-1) + 3^(n-1), both like A005061 (note for A005061 dual formula a(n) = 3*a(n-1) + 4^(n-1) = 3*a(n-1) + A000302(n-1)).
a(n) = 3*a(n-1) + 2^(2n+1) = 3*a(n-1) + A004171(n).
a(n) = A005061(n) + A000302(n).
b(n) = mix(A005061, A085350) = 0,1,1,5,7,23,... = differences of (A167762 = 0,0,1,2,7,14,37,...); b(n) differences = A167784. (End)

A085352 Expansion of (1-4x)/((1-5x)(1-6x)).

Original entry on oeis.org

1, 7, 47, 307, 1967, 12427, 77687, 481747, 2968607, 18202267, 111166727, 676765987, 4109424047, 24900684907, 150624812567, 909852391027, 5489631924287, 33090379436347, 199305216071207, 1199645993692867
Offset: 0

Views

Author

Paul Barry, Jun 24 2003

Keywords

Comments

Binomial transform of A085351. Binomial transform is A085353.

Crossrefs

Programs

  • PARI
    Vec((1 - 4*x) / ((1 - 5*x)*(1 - 6*x)) + O(x^20)) \\ Colin Barker, Jul 07 2020

Formula

a(n) = 2*6^n - 5^n.
a(n) = 11*a(n-1) - 30*a(n-2) for n>1. - Colin Barker, Jul 07 2020

A097165 Expansion of (1-3x)/((1-x)(1-4x)(1-5x)).

Original entry on oeis.org

1, 7, 41, 227, 1221, 6447, 33601, 173467, 889181, 4533287, 23015961, 116477907, 587981941, 2962279327, 14900875121, 74862289547, 375743103501, 1884442140567, 9445117195081, 47317211944387, 236952563597861
Offset: 0

Views

Author

Paul Barry, Jul 30 2004

Keywords

Comments

Partial sums of A085351. Convolution of A034478 and 4^n. Convolution of A047849 and 5^n. a(n)=A097162(2n+1)/3. Third binomial transform of A097164.

Programs

  • Mathematica
    CoefficientList[Series[(1-3x)/((1-x)(1-4x)(1-5x)),{x,0,30}],x] (* or *) LinearRecurrence[{10,-29,20},{1,7,41},30] (* Harvey P. Dale, Jan 24 2012 *)

Formula

a(n)=5*5^n/2-4*4^n/3-1/6; a(n)=sum{k=0..n, (5^k+1)4^(n-k)/2}; a(n)=sum{k=0..n, (4^k+2)5^(n-k)/3}; a(n)=10a(n-1)-29a(n-2)+20a(n-3).
Showing 1-3 of 3 results.