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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.

A244140 Triangle read by rows: coefficients T(n,k) of a binomial decomposition of n*(-1)^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, 0, -3, 0, 0, 0, -3, 16, 0, 0, 0, -3, 32, -135, 0, 0, 0, -3, 64, -405, 1536, 0, 0, 0, -3, 128, -1215, 6144, -21875, 0, 0, 0, -3, 256, -3645, 24576, -109375, 373248, 0, 0, 0, -3, 512, -10935, 98304, -546875, 2239488, -7411887, 0, 0, 0, -3, 1024, -32805, 393216, -2734375, 13436928, -51883209, 167772160
Offset: 0

Views

Author

Stanislav Sykora, Jun 23 2014

Keywords

Comments

T(n,k)=(-1)^k*k*(k-2)^(n-2) for k>1, while T(n,0)=0 and T(1,1)=-0^(n-1) by convention.

Examples

			The first rows of the triangle are:
0,
0, -1,
0, 0, 2,
0, 0, 0, -3,
0, 0, 0, -3, 16,
0, 0, 0, -3, 32, -135,
0, 0, 0, -3, 64, -405, 1536,
0, 0, 0, -3, 128, -1215, 6144, -21875,
		

Crossrefs

Programs

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