A393789 Expansion of e.g.f. 1 / (2 - exp(x))^exp(x).

1, 1, 5, 28, 199, 1726, 17559, 204520, 2681935, 39082474, 626351143, 10946428252, 207149346903, 4219505352934, 92041853869255, 2140562522028904, 52868915720090143, 1382006260803205186, 38117747649294996999, 1106267413537559712916, 33700299399500131793575, 1075161369865015739205310

Offset

0,3

Links

Table of n, a(n) for n=0..21.

Formula

a(n) = Sum_{k=0..n} Stirling2(n,k) * A073479(k).

a(n) ~ sqrt(Pi) * n^(n + 3/2) / (2^(3/2) * exp(n) * log(2)^(n+2)). - Vaclav Kotesovec, Feb 27 2026

Mathematica

nmax = 21; CoefficientList[Series[1/(2 - Exp[x])^Exp[x], {x, 0, nmax}], x] Range[0, nmax]!

Crossrefs

Cf. A000670, A005649, A073479, A143405, A191365, A354413.

Sequence in context: A240770 A318364 A064898 * A368792 A216586 A151500

Adjacent sequences: A393786 A393787 A393788 * A393790 A393791 A393792

Keyword

nonn

Author

Ilya Gutkovskiy, Feb 27 2026

Status

approved