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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.

A244121 Triangle read by rows: terms T(n,k) of a binomial decomposition of n^n as Sum(k=0..n)T(n,k).

Original entry on oeis.org

1, 0, 1, 0, 4, 0, 0, 9, 18, 0, 0, 16, 192, 48, 0, 0, 25, 1200, 1800, 100, 0, 0, 36, 5760, 29160, 11520, 180, 0, 0, 49, 23520, 317520, 423360, 58800, 294, 0, 0, 64, 86016, 2721600, 9175040, 4536000, 258048, 448, 0, 0, 81, 290304, 19840464, 145152000, 181440000, 39680928, 1016064, 648, 0
Offset: 0

Views

Author

Stanislav Sykora, Jun 21 2014

Keywords

Comments

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

Examples

			First rows of the triangle, all summing up to n^n:
1
0 1
0 4   0
0 9  18   0
0 16 192  48  0
0 25 1200 1800 100 0
		

Crossrefs

Programs

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