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.

A132611 Column 0 of triangle A132610.

Original entry on oeis.org

1, 1, 2, 14, 194, 4114, 118042, 4274612, 186932958, 9577713250, 562450162646, 37232881004442, 2742420824107648, 222414345991567630, 19691735781407563460, 1889658596054736522248, 195353325211864635176182, 21643625444562045727620930
Offset: 0

Views

Author

Paul D. Hanna, Aug 23 2007

Keywords

Comments

Triangle T=A132610 is generated by even matrix powers of itself such that row n+1 of T = row n of T^(2n) with appended '1' for n>=0 with T(0,0)=1.

Crossrefs

Cf. A132610 (triangle); other columns: A132612, A132613; A132614.

Programs

  • PARI
    {a(n)=local(k=0,A=vector(n+1), p); A[1]=1; for(j=1, n-k-1, p=(n-1)^2-(n-j-1)^2; A=Vec((Polrev(A)+x*O(x^p))/(1-x))); A=Vec((Polrev(A)+x*O(x^p))/(1-x)); A[p+1]}
    for(n=0,25,print1(a(n),", "))
    
  • PARI
    {a(n)=local(A=[1]);for(i=1,n,A=Vec(Ser(A)/(1-x)^(2*(#A)-3));A=concat(A,A[#A]));A[#A]}
    for(n=0,25,print1(a(n),", "))