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.

A171660 Triangle T(n,m) of the expansion coefficients of JacobiCN(x,y) + JacobiDN(x,y) = Sum_{n>=0} Sum_{k=0..n} (-1)^n*T(n,m)*x^(2*n)*y^(2*m)/(2*n)!.

Original entry on oeis.org

2, 1, 1, 1, 8, 1, 1, 60, 60, 1, 1, 472, 1824, 472, 1, 1, 3944, 46576, 46576, 3944, 1, 1, 34236, 1129968, 3077120, 1129968, 34236, 1, 1, 303028, 27126048, 171931904, 171931904, 27126048, 303028, 1, 1, 2706800, 653677408, 8874639488, 19720976896
Offset: 0

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Author

Roger L. Bagula, Dec 14 2009

Keywords

Comments

Row sums are 2*A000364(n).
Since the coefficients of JacobiCN are in A060627 and the coefficients of JacobiDN are obtained by row-reversal of A060627, this triangle here is a symmetrized variant, adding A060627 and its mirrored version.

Examples

			2;
1, 1;
1, 8, 1;
1, 60, 60, 1;
1, 472, 1824, 472, 1;
1, 3944, 46576, 46576, 3944, 1;
1, 34236, 1129968, 3077120, 1129968, 34236, 1;
1, 303028, 27126048, 171931904, 171931904, 27126048, 303028, 1;
1, 2706800, 653677408, 8874639488, 19720976896, 8874639488, 653677408, 2706800, 1;
1, 24279312, 15877769376, 440712200064, 1948265426688, 1948265426688, 440712200064, 15877769376, 24279312, 1;
1, 218186164, 388726995744, 21489645169920, 176743676925696, 343497841920000, 176743676925696, 21489645169920, 388726995744, 218186164, 1;
		

Crossrefs

Cf. A060627.

Programs

  • Maple
    A171660 := proc(n,m) JacobiCN(z,k) +JacobiDN(z,k) ; coeftayl(%,z=0,2*n) ; (-1)^n*coeftayl(%,k=0,2*m)*(2*n)! ; end proc: # R. J. Mathar, Jan 30 2011
  • Mathematica
    p[t_] = JacobiCN[t, x] + JacobiDN[t, x]
    a = Table[ CoefficientList[FullSimplify[ExpandAll[(-1)^Floor[n/2]*n!*SeriesCoefficient[ Series[p[t], {t, 0, 30}], n]]], x], {n, 0, 20, 2}]
    Flatten[a]