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.

A244132 Triangle read by rows: coefficients T(n,k) of a binomial decomposition of n as Sum(k=0..n)T(n,k)*binomial(n,k).

Original entry on oeis.org

0, 0, 1, 0, 0, 2, 0, 0, -2, 9, 0, 0, 2, -18, 64, 0, 0, -2, 36, -192, 625, 0, 0, 2, -72, 576, -2500, 7776, 0, 0, -2, 144, -1728, 10000, -38880, 117649, 0, 0, 2, -288, 5184, -40000, 194400, -705894, 2097152, 0, 0, -2, 576, -15552, 160000, -972000, 4235364, -14680064, 43046721
Offset: 0

Views

Author

Stanislav Sykora, Jun 22 2014

Keywords

Comments

T(n,k)=(k)^(k-1)*(1-k)^(n-k) for k>0, while T(n,0)=0 by convention.

Examples

			The first rows of the triangle are:
0,
0, 1,
0, 0, 2,
0, 0, -2, 9,
0, 0, 2, -18, 64,
0, 0, -2, 36, -192, 625,
		

Crossrefs

Programs

  • PARI
    seq(nmax, b)={my(v, n, k, irow);
    v = vector((nmax+1)*(nmax+2)/2); v[1]=0;
    for(n=1, nmax, irow=1+n*(n+1)/2; v[irow]=0;
      for(k=1, n, v[irow+k]=(-k*b)^(k-1)*(1+k*b)^(n-k); ); );
    return(v); }
    a=seq(100,-1);