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A303566
a(n) = [x^n] (Sum_{k=0..n} (k+1)!*x^k)/(Sum_{k=0..n} (k+1)!*(-x)^k).
3
1, 4, 8, 40, 128, 1168, 4448, 66400, 268544, 6124480, 25118336, 827294848, 3386501120, 153439657216, 624706655744, 37378784384512, 151446759993344, 11573673369828352, 46729404312578048, 4439994292732364800, 17884613664930529280, 2067374053521268559872
OFFSET
0,2
LINKS
PROG
(PARI) N=66; x='x+O('x^N); Vec(sum(k=0, N, (k+1)!*x^k)/sum(k=0, N, (k+1)!*(-x)^k))
CROSSREFS
Sequence in context: A343810 A165458 A009335 * A165622 A162076 A137047
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Apr 26 2018
STATUS
approved