OFFSET
0,3
LINKS
Robert Israel, Table of n, a(n) for n = 0..444
Vladimir Kruchinin and D. V. Kruchinin, Composita and their properties, arXiv:1103.2582 [math.CO], 2011-2013.
FORMULA
a(n) = Sum_{m=1..n} (Sum_{k=m..n} (k!*binomial(m,k-m)*2^(k-m)*Stirling1(n,k))/m!), n > 0, a(0) = 1.
MAPLE
S:= series(exp(log(1+x)+2*log(1+x)^2), x, 31):
seq(coeff(S, x, j)*j!, j=0..30); # Robert Israel, Jan 30 2018
MATHEMATICA
With[{nn=20}, CoefficientList[Series[Exp[Log[1+x]+2Log[1+x]^2], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Dec 27 2014 *)
PROG
(Maxima)
a(n):=sum(sum(k!*binomial(m, k-m)*2^(k-m)*stirling1(n, k), k, m, n)/m!, m, 1, n);
CROSSREFS
KEYWORD
sign
AUTHOR
Vladimir Kruchinin, Apr 21 2011
STATUS
approved