OFFSET
0,4
LINKS
Robert Israel, Table of n, a(n) for n = 0..297
Eric Weisstein's World of Mathematics, Complementary Bell Number
FORMULA
a(n) = Sum_{k=0..2*n} (-1)^k*Stirling2(2*n,k).
a(n) = A000587(2*n).
MAPLE
seq(BellB(2*n, -1), n=0..30); # Robert Israel, Jun 08 2020
MATHEMATICA
Table[Exp[1] Sum[(-1)^k k^(2 n)/k!, {k, 0, Infinity}], {n, 0, 19}]
Table[BellB[2 n, -1], {n, 0, 19}]
CROSSREFS
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Jun 13 2019
STATUS
approved