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A308337 Expansion of e.g.f. exp(-1 + Product_{k>=1} 1/(1 - x^k/k)). 2
1, 1, 4, 21, 146, 1210, 11894, 133000, 1677668, 23439684, 359651232, 6000427884, 108157599120, 2092493844480, 43240336406136, 950021322002904, 22108068716440272, 543048769028068944, 14037848562783308160, 380851191359082217488, 10818262594065294568416 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..20.

FORMULA

a(0) = 1; a(n) = Sum_{k=1..n} binomial(n-1,k-1)*A007841(k)*a(n-k).

MATHEMATICA

nmax = 20; CoefficientList[Series[Exp[Product[1/(1 - x^k/k), {k, 1, nmax}] - 1], {x, 0, nmax}], x] Range[0, nmax]!

CROSSREFS

Cf. A007841, A143463, A308338.

Sequence in context: A228111 A305986 A233481 * A307525 A327872 A163861

Adjacent sequences:  A308334 A308335 A308336 * A308338 A308339 A308340

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, May 20 2019

STATUS

approved

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Last modified February 19 13:25 EST 2020. Contains 332044 sequences. (Running on oeis4.)