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A357089
E.g.f. satisfies A(x) * log(A(x)) = (exp(x*A(x)) - 1)^3 / 6.
2
1, 0, 0, 1, 6, 25, 140, 1561, 19586, 228425, 2870160, 44172601, 780614846, 14499946825, 284310704860, 6089231941521, 142225796401786, 3537029819020905, 92766573133851240, 2577870903366020521, 75999605064376599606, 2362944241092314079145
OFFSET
0,5
FORMULA
a(n) = Sum_{k=0..floor(n/3)} (3*k)! * (n-k+1)^(k-1) * Stirling2(n,3*k)/(6^k * k!).
PROG
(PARI) a(n) = sum(k=0, n\3, (3*k)!*(n-k+1)^(k-1)*stirling(n, 3*k, 2)/(6^k*k!));
CROSSREFS
Sequence in context: A136593 A012293 A012594 * A242858 A200375 A009464
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 11 2022
STATUS
approved