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.

A341809 Number of ways to write n as an ordered sum of 10 nonzero tetrahedral numbers.

Original entry on oeis.org

1, 0, 0, 10, 0, 0, 45, 0, 0, 130, 0, 0, 300, 0, 0, 612, 0, 0, 1095, 10, 0, 1740, 90, 0, 2565, 360, 0, 3490, 930, 0, 4351, 1980, 0, 5130, 3790, 0, 5680, 6330, 45, 5820, 9540, 360, 5715, 13620, 1260, 5292, 17950, 2880, 4530, 22140, 5670, 3780, 26490, 10170, 2940, 29770, 15840
Offset: 10

Views

Author

Ilya Gutkovskiy, Feb 20 2021

Keywords

Crossrefs

Programs

  • Magma
    R:=PowerSeriesRing(Integers(), 70);
    Coefficients(R!( (&+[x^Binomial(j+2,3): j in [1..70]])^10 )); // G. C. Greubel, Jul 18 2022
    
  • Mathematica
    nmax = 66; CoefficientList[Series[Sum[x^Binomial[k + 2, 3], {k, 1, nmax}]^10, {x, 0, nmax}], x] // Drop[#, 10] &
  • Sage
    def f(m, x): return ( sum( x^(binomial(j+2,3)) for j in (1..8) ) )^m
    def A341809_list(prec):
        P. = PowerSeriesRing(ZZ, prec)
        return P( f(10, x) ).list()
    a=A341809_list(100); a[10:71]  # G. C. Greubel, Jul 18 2022

Formula

G.f.: ( Sum_{k>=1} x^binomial(k+2,3) )^10.