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.

A309301 (1/9) times the sum of the elements of all subsets of [n] whose sum is divisible by nine.

Original entry on oeis.org

0, 0, 0, 0, 1, 3, 9, 23, 60, 150, 354, 843, 1983, 4608, 10638, 24318, 55043, 123862, 276868, 614996, 1359446, 2990726, 6550528, 14292132, 31069860, 67316446, 145403700, 313177200, 672746880, 1441600632, 3082042512, 6575014400, 13998418584, 29746639512
Offset: 0

Views

Author

Alois P. Heinz, Jul 21 2019

Keywords

Crossrefs

Column k=9 of A309280.

Formula

G.f.: -x^4*(64*x^33-160*x^30+32*x^29+80*x^28+216*x^27+96*x^26 -312*x^25 -160*x^24 -200*x^23 +376*x^22+40*x^21 -4*x^20+164*x^19-48*x^18 +60*x^17 -516*x^16 +114*x^15+4*x^14+340*x^13-79*x^12-30*x^11-78*x^10 +4*x^9 +45*x^8 -33*x^7+20*x^6-24*x^5+24*x^4-9*x^3+3*x^2 -3*x+1) / ((2*x-1)^3 *(2*x^3-1)^3 *(2*x^9-1)^3).