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A032299
"EFJ" (unordered, size, labeled) transform of 1,2,3,4,...
6
1, 1, 2, 9, 16, 85, 516, 1519, 6280, 45441, 431740, 1394371, 8370924, 43960657, 459099018, 6135631545, 23813007376, 150537761905, 1029390040764, 7519458731131, 101693768415220, 1909742186139921, 8269148260309882, 60924484457661793, 417027498430063800
OFFSET
0,3
LINKS
C. G. Bower, Transforms (2)
FORMULA
E.g.f.: Product_{m>0} (1+x^m/(m-1)!). - Vladeta Jovovic, Nov 26 2002
E.g.f.: exp(Sum_{k>=1} Sum_{j>=1} (-1)^(k+1)*x^(j*k)/(k*((j - 1)!)^k)). - Ilya Gutkovskiy, Sep 13 2018
MATHEMATICA
mmax = 25;
egf = Product[1 + x^m/(m - 1)!, {m, 1, mmax}] + O[x]^mmax;
CoefficientList[egf, x] * Range[0, mmax - 1]! (* Jean-François Alcover, Sep 23 2019 *)
PROG
(PARI) seq(n)={Vec(serlaplace(prod(k=1, n, 1 + k*x^k/k! + O(x*x^n))))} \\ Andrew Howroyd, Sep 11 2018
CROSSREFS
Sequence in context: A075645 A185252 A055259 * A032211 A032136 A032040
KEYWORD
nonn
EXTENSIONS
a(0)=1 prepended and terms a(23) and beyond from Andrew Howroyd, Sep 11 2018
STATUS
approved