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.

A178118 Antidiagonal sums of the triangle A060187.

Original entry on oeis.org

0, 1, 1, 2, 7, 25, 100, 469, 2481, 14406, 90995, 621553, 4561112, 35736921, 297435521, 2618575194, 24297706927, 236870849417, 2419213831452, 25820011544781, 287327296473585, 3326999636488190, 40011485288491131
Offset: 0

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Author

Roger L. Bagula, May 20 2010

Keywords

Comments

This sequence is an analog to the Lucas formula which obtains A000045 as the antidiagonal sums of the Pascal triangle A007318.

References

  • David M. Burton, Elementary number theory, McGraw Hill (2002), page 286

Crossrefs

Programs

  • Mathematica
    p[x_, n_] = (1 - x)^(n + 1)*Sum[(2*k + 1)^n*x^k, {k, 0, Infinity}];
    f[n_, m_] := CoefficientList[FullSimplify[ExpandAll[p[x, n]]], x][[m + 1]]
    a[n_] := Sum[f[n - m - 1, m], {m, 0, Floor[(n - 1)/2]}]
    Table[a[n], {n, 0, 30}]

Formula

a(n) = sum_{m=0.. floor[(n-1)/2]} A060187(n-m-1,m).

Extensions

Exact definition moved to formula - the Assoc. Eds. of the OEIS, Aug 20 2010