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A377490
E.g.f. satisfies A(x) = 1/(1 - A(x) * (exp(x*A(x)) - 1))^2.
2
1, 2, 24, 560, 19844, 949632, 57398980, 4197775472, 360541351092, 35581415127200, 3968076446262116, 493536896206210320, 67738259336620421140, 10170114513821104697792, 1658107523049271429191492, 291735781263854493014688944, 55097256018925972909190946932
OFFSET
0,2
FORMULA
E.g.f.: B(x)^2, where B(x) is the e.g.f. of A377495.
a(n) = 2 * Sum_{k=0..n} (2*n+3*k+1)!/(2*n+2*k+2)! * Stirling2(n,k).
PROG
(PARI) a(n) = 2*sum(k=0, n, (2*n+3*k+1)!/(2*n+2*k+2)!*stirling(n, k, 2));
CROSSREFS
Cf. A377495.
Sequence in context: A210905 A012113 A156525 * A377492 A377425 A170904
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 29 2024
STATUS
approved