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.

A187548 Alternating partial sums of L(n)*H(n+1), product of central Lah number L(n) and Harmonic number H(n+1).

Original entry on oeis.org

1, 2, 64, 2436, 131824, 9203264, 787735648, 79884060128, 9366719620672, 1246887723480128, 185786630586649792, 30635253866287585088, 5538860010787064796352, 1089574788981508858403648, 231683608824013918904796352, 52954849085008593516185123648
Offset: 0

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Author

Emanuele Munarini, Mar 11 2011

Keywords

Crossrefs

Programs

  • Maple
    H := proc(n) add(1/i,i=1..n) ; end proc:
    A187535 := proc(n) if n=0 then 1; else binomial(2*n-1, n-1)*(2*n)!/n! end if; end proc:
    A187547 := proc(n) H(n+1)*A187535(n) ; end proc:
    A187548 := proc(n) add( A187547(k)*(-1)^(n-k),k=0..n) ; end proc:
    seq(A187548(n),n=0..20) ; # R. J. Mathar, Mar 24 2011
  • Mathematica
    Table[Sum[(-1)^n+(-1)^(n-k)Binomial[2k-1,k-1](2k)!/k!HarmonicNumber[k+1],{k,1,n}],{n,0,12}]
  • Maxima
    makelist((-1)^n+sum((-1)^(n-k)*binomial(2*k-1,k-1)*(2*k)!/k!*sum(1/i,i,1,k+1),k,1,n),n,0,12);

Formula

a(n) = Sum_{k=0..n} (-1)^(n-k)*A187547(k).