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.

A155163 Triangle T(n,k): the coefficient of [x^k] of the series -(x-1)^(2*n+1) *Sum_{j>=0} (j+1)^n *binomial(j,n) * x^(j-n); columns 0<=k

Original entry on oeis.org

2, 9, 3, 64, 52, 4, 625, 855, 195, 5, 7776, 15306, 6546, 606, 6, 117649, 305571, 201866, 38486, 1701, 7, 2097152, 6806472, 6244680, 1950320, 194160, 4488, 8, 43046721, 168205743, 200503701, 90665595, 15597315, 887949, 11367, 9
Offset: 1

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Author

Roger L. Bagula and Gary W. Adamson, Jan 21 2009

Keywords

Comments

Row sums are A001813: 2, 12, 120, 1680, 30240, 665280, 17297280, 518918400.

Examples

			[n\k][     0           1          2        3         4       5      6   7]
[1]        2;
[2]        9,         3;
[3]       64,        52,         4;
[4]      625,       855,       195,        5;
[5]     7776,     15306,      6546,      606,        6;
[6]   117649,    305571,    201866,    38486,     1701,      7;
[7]  2097152,   6806472,   6244680,  1950320,   194160,   4488,     8;
[8] 43046721, 168205743, 200503701, 90665595, 15597315, 887949, 11367, 9;
		

Crossrefs

Cf. A202017.

Programs

  • GAP
    T := Flat(List([1..50], n->List([1..n], m->Sum([1..n], k->Factorial(k) * (-1)^(n+m+k+1) * Stirling2(n,k) * Binomial(n-k,m-1) * Binomial(n+k,k))))); # Muniru A Asiru, Jan 27 2018
  • Maple
    A155163 := proc(n,k)
            -(x-1)^(2*n+1)*add(x^(j-n)*(j+1)^n*binomial(j,n),j=0..n+10) ;
            coeftayl(%,x=0,k) ;
    end proc: # R. J. Mathar, Feb 13 2013
  • Mathematica
    Clear[p, x, n, m]; p[x_, n_] = -((x - 1)^(2*n + 1)/x^n)*Sum[( k + 1)^n*Binomial[k, n]*x^k, {k, 0, Infinity}];
    Table[FullSimplify[ExpandAll[p[x, n]]], {n, 0, 10}];
    Table[CoefficientList[FullSimplify[ExpandAll[p[x, n]]], x], {n, 0, 10}];
    Flatten[%]
  • Maxima
    T(n,m):=sum(k!*(-1)^(n+m+k+1)*stirling2(n,k)*binomial(n-k,m-1)*binomial(n+k,k),k,1,n); /* Vladimir Kruchinin, Jan 27 2018 */
    

Formula

T(n,m) = Sum_{k=1..n} k!*(-1)^(n+m+k+1)*Stirling2(n,k)*C(n-k,m-1)*C(n+k,k). - Vladimir Kruchinin, Jan 27 2018
E.g.f. A(x,y) = E(A(x,y),y), where E(x,y)=(1-y)/(exp(x*(y-1))-y) - e.g.f. Eulerian numbers (A173018). - Vladimir Kruchinin, Aug 31 2018