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.

A105628 Row sums of triangle A105626.

Original entry on oeis.org

1, 4, 25, 208, 2152, 26524, 378700, 6142948, 111593932, 2244992404, 49561796380, 1191625266388, 31001841211852, 867899276874964, 26017959787456060, 831650920910208628, 28237504357447540972, 1014987937635390612724
Offset: 0

Views

Author

Paul D. Hanna, Apr 16 2005

Keywords

Comments

A105626 equals the cube of the matrix square-root of triangle A105615.

Crossrefs

Programs

  • PARI
    {a(n)=local(R,M=matrix(n+3,n+3,m,j,if(m>=j,if(m==j,1,if(m==j+1,-2*j, polcoeff(1/sum(i=0,m-j,(2*i)!/i!/2^i*x^i)+O(x^m),m-j)))))^-3); R=(M+M^0)/2;for(i=1,floor(2*log(n+2)),R=(R+M*R^(-1))/2); return(if(n<0,0,sum(k=0,n,R[n+1,k+1])))}