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.

A029032 Expansion of 1/((1-x)*(1-x^3)*(1-x^4)*(1-x^5)).

Original entry on oeis.org

1, 1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 17, 20, 23, 27, 31, 35, 40, 45, 51, 57, 63, 70, 78, 86, 94, 103, 113, 123, 134, 145, 157, 170, 183, 197, 212, 227, 243, 260, 278, 296, 315, 335, 356, 378, 400, 423, 448, 473, 499, 526, 554, 583, 613, 644, 676, 709, 743
Offset: 0

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Keywords

Comments

a(n) is the number of partitions of n into parts 1, 3, 4, and 5. - David Neil McGrath, Sep 13 2014

Programs

  • Maple
    M := Matrix(13, (i,j)-> if (i=j-1) or (j=1 and member(i, [1, 3, 10, 12])) then 1 elif j=1 and member(i, [6, 7, 13]) then -1 else 0 fi); a := n -> (M^(n))[1,1]; seq (a(n), n=0..49); # Alois P. Heinz, Jul 25 2008
  • Mathematica
    CoefficientList[Series[1/((1-x)(1-x^3)(1-x^4)(1-x^5)),{x,0,50}],x] (* Harvey P. Dale, Jan 04 2012 *)

Formula

a(0)=1, a(1)=1, a(2)=1, a(3)=2, a(4)=3, a(5)=4, a(6)=5, a(7)=6, a(8)=8, a(9)=10, a(10)=12, a(11)=14, a(12)=17, a(n)=a(n-1)+a(n-3)-a(n-6)- a(n-7)+ a(n-10)+a(n-12)-a (n-13). - Harvey P. Dale, Jan 04 2012
From R. J. Mathar, Jun 23 2021: (Start)
a(n)-a(n-1) = A008680(n).
a(n)-a(n-3) = A025772(n).
a(n)-a(n-4) = A008672(n).
a(n)-a(n-5) = A025767(n). (End)
a(n) = 1 + floor((2*n^3+39*n^2+228*n)/720). - Hoang Xuan Thanh, May 29 2025