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.

A275640 Expansion of (1-q)^k/Product_{j=1..k} (1-q^j) for k=6.

Original entry on oeis.org

1, -5, 11, -14, 12, -9, 9, -13, 20, -26, 27, -25, 26, -33, 43, -49, 47, -42, 43, -53, 67, -77, 78, -73, 72, -82, 98, -108, 107, -102, 104, -118, 138, -151, 150, -142, 141, -155, 178, -194, 194, -187, 189, -206, 230, -246, 245, -235, 235, -255, 285, -305, 305, -295, 295, -315, 345, -365, 365
Offset: 0

Views

Author

N. J. A. Sloane, Aug 09 2016

Keywords

Crossrefs

Cf. A275638.

Programs

  • Mathematica
    CoefficientList[Series[1/((1+x)^3(1-x+x^2)(1+x^2)(1+x+x^2)^2(1+ x+x^2+ x^3+x^4)),{x,0,100}],x] (* or *) LinearRecurrence[{-5,-14,-29,-49,-71,-90,-101,-101,-90,-71,-49,-29,-14,-5,-1},{1,-5,11,-14,12,-9,9,-13,20,-26,27,-25,26,-33,43},100] (* Harvey P. Dale, Mar 14 2023 *)

Formula

Equivalent g.f.: 1 / ((1+x)^3*(1-x+x^2)*(1+x^2)*(1+x+x^2)^2*(1+x+x^2+x^3+x^4)). - Colin Barker, Aug 10 2016