OFFSET
0,6
COMMENTS
Logarithmic transform of A000041.
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..483
N. J. A. Sloane, Transforms
FORMULA
E.g.f.: log(Sum_{k>=0} A000041(k)*x^k/k!).
EXAMPLE
E.g.f.: A(x) = x/1! + x^2/2! - x^3/3! - x^4/4! + 6*x^5/5! - x^6/6! - 77*x^7/7! + 203*x^8/8! + ...
MAPLE
a:= proc(n) option remember; (t-> `if`(n=0, 0, t(n)-add(j*a(j)*
binomial(n, j)*t(n-j), j=1..n-1)/n))(combinat[numbpart])
end:
seq(a(n), n=0..30); # Alois P. Heinz, Mar 07 2018
MATHEMATICA
nmax = 25; CoefficientList[Series[Log[Sum[PartitionsP[k] x^k/k!, {k, 0, nmax}]], {x, 0, nmax}], x] Range[0, nmax]!
a[n_] := a[n] = PartitionsP[n] - Sum[k Binomial[n, k] PartitionsP[n - k] a[k], {k, 1, n - 1}]/n; a[0] = 0; Table[a[n], {n, 0, 25}]
CROSSREFS
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Mar 07 2018
STATUS
approved