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.

A178619 Triangle T(n,k) with the coefficient of [x^k] of the series (1-x)^(n+1)* sum_{j>=0} binomial(n + 4*j, 4*j)*x^j in row n, column k.

Original entry on oeis.org

1, 1, 3, 1, 12, 3, 1, 31, 31, 1, 1, 65, 155, 35, 1, 120, 546, 336, 21, 1, 203, 1554, 1918, 413, 7, 1, 322, 3823, 8092, 3823, 322, 1, 1, 486, 8451, 27876, 23607, 4950, 165, 1, 705, 17205, 82885, 112035, 44803, 4455, 55, 1, 990, 32802, 220198, 440484, 291258
Offset: 0

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Author

Roger L. Bagula, May 30 2010

Keywords

Comments

Every fourth row is symmetrical.
Row sums are 4^n.
3*k instead of 4*k in the binomial() gives A178618.

Examples

			1;
1, 3;
1, 12, 3;
1, 31, 31, 1;
1, 65, 155, 35;
1, 120, 546, 336, 21;
1, 203, 1554, 1918, 413, 7;
1, 322, 3823, 8092, 3823, 322, 1;
1, 486, 8451, 27876, 23607, 4950, 165;
1, 705, 17205, 82885, 112035, 44803, 4455, 55;
1, 990, 32802, 220198, 440484, 291258, 59950, 2882, 11;
		

Crossrefs

Programs

  • Maple
    A178619 := proc(n,k)
        (1-x)^(n+1)*add( binomial(n+4*j,4*j)*x^j,j=0..n+1) ;
        coeftayl(%,x=0,k) ;
    end proc:
    seq(seq(A178619(n,k),k=0..n),n=0..8) ; # R. J. Mathar, Nov 05 2012
  • Mathematica
    p[x_, n_] = (-1)^(n + 1)*(-1 + x)^(n + 1)*Sum[Binomial[n + 4*k, 4*k]*x^k, {k, 0, Infinity}]
    Flatten[Table[CoefficientList[FullSimplify[ExpandAll[p[x, n]]], x], {n, 0, 10}]]