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.

A223173 Poly-Cauchy numbers c_3^(-n).

Original entry on oeis.org

-1, -3, -1, 45, 359, 2037, 10079, 46365, 204119, 873477, 3666959, 15191085, 62342279, 254119317, 1030760639, 4165958205, 16792710839, 67557739557, 271392171119, 1089053371725, 4366669645799, 17498051254197, 70086331418399, 280627721655645
Offset: 1

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Author

Takao Komatsu, Mar 28 2013

Keywords

Comments

Definition of poly-Cauchy numbers in A222627.

Programs

  • Magma
    [&+[StirlingFirst(3,k)*(k+1)^n: k in [0..3]]: n in [1..25]]; // Bruno Berselli, Mar 28 2013
    
  • Maple
    seq(2^(n+1)-3^(n+1)+4^n, n=0..30); # Robert Israel, Jun 21 2018
  • Mathematica
    Table[Sum[StirlingS1[3, k] (k + 1)^n, {k, 0, 3}], {n, 25}]
  • PARI
    a(n) = sum(k=0, 3, stirling(3, k, 1)*(k+1)^n); \\ Michel Marcus, Nov 14 2015

Formula

a(n) = Sum_{k=0..3} Stirling1(3,k)*(k+1)^n.
From Colin Barker, Mar 31 2013: (Start)
Conjecture:
a(n) = 2^(1+n) - 3^(1+n) + 4^n;
g.f.: -x*(6*x-1) / ((2*x-1)*(3*x-1)*(4*x-1)). (End)
Conjecture verified by Robert Israel, Jun 21 2018