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.

A147851 Expansion of 1/(1 - x^3 - x^4 - x^5 + x^8)^2.

Original entry on oeis.org

1, 0, 0, 2, 2, 2, 3, 6, 7, 10, 15, 18, 27, 38, 50, 66, 92, 126, 165, 224, 300, 400, 536, 714, 948, 1258, 1676, 2218, 2932, 3882, 5128, 6768, 8924, 11760, 15479, 20366, 26780, 35174, 46182, 60602, 79473, 104158, 136445, 178654, 233797, 305834, 399881
Offset: 0

Views

Author

Roger L. Bagula, Nov 15 2008

Keywords

Crossrefs

Programs

  • Magma
    m:=50; R:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/(1 -x^3-x^4-x^5+x^8)^2)); // G. C. Greubel, Nov 03 2018
  • Mathematica
    CoefficientList[Series[1/(1 - x^3 - x^4 - x^5 + x^8)^2, {x, 0, 50}], x]
  • PARI
    x='x+O('x^50); Vec(1/(1-x^3-x^4-x^5+x^8)^2) \\ G. C. Greubel, Nov 03 2018
    

Formula

a(n) = 2*a(n-3) + 2*a(n-4) + 2*a(n-5) - a(n-6) - 2*a(n-7) - 5*a(n-8) - 2*a(n-9) - a(n-10) + 2*a(n-11) + 2*a(n-12) + 2*a(n-13) - a(n-16). - Franck Maminirina Ramaharo, Nov 02 2018

Extensions

Name clarified by Franck Maminirina Ramaharo, Nov 02 2018