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.

A276042 Exponential convolution of central polygonal numbers (A000124) with themselves.

Original entry on oeis.org

1, 4, 16, 62, 230, 812, 2728, 8752, 26944, 80000, 230144, 644096, 1759744, 4707328, 12359680, 31920128, 81231872, 204013568, 506331136, 1243217920, 3022913536, 7285243904, 17415274496, 41321234432, 97370767360, 227993976832, 530713673728
Offset: 0

Views

Author

Ilya Gutkovskiy, Aug 27 2016

Keywords

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{10, -40, 80, -80, 32}, {1, 4, 16, 62, 230}, 27]
    Table[2^(n - 6) (n^4 + 2 n^3 + 19 n^2 + 42 n + 64), {n, 0, 26}]

Formula

O.g.f.: (1 - 6*x + 16*x^2 - 18*x^3 + 10*x^4)/(1 - 2*x)^5.
E.g.f.: (2 + 2*x + x^2)^2*exp(2*x)/4.
a(n) = 10*a(n-1) - 40*a(n-2) + 80*a(n-3) - 80*a(n-4) + 32*a(n-5).
a(n) = 2^(n - 6)*(n^4 + 2*n^3 + 19*n^2 + 42*n + 64).