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A227044 a(n) = Sum_{k>=1} k^(2*n)/(2^k). 1
1, 6, 150, 9366, 1091670, 204495126, 56183135190, 21282685940886, 10631309363962710, 6771069326513690646, 5355375592488768406230, 5149688839606380769088406, 5916558242148290945301297750, 8004451519688336984972255078166, 12595124129900132067036747870669270 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..100

FORMULA

a(n) ~ (2n)!/(log(2))^(2*n+1).

a(n) = Sum_{k=0..2*n} (-2)^k * k! * Stirling2(2*n, k). - Paul D. Hanna, Apr 15 2018

MATHEMATICA

Table[Sum[k^(2*n)/(2^k), {k, 1, Infinity}], {n, 0, 20}]

PROG

(PARI) {a(n) = sum(k=0, 2*n, (-2)^k * k! * stirling(2*n, k, 2) )}

for(n=0, 20, print1(a(n), ", "))

CROSSREFS

Cf. A000629, A080163.

Sequence in context: A013296 A013301 A233734 * A188420 A089482 A126679

Adjacent sequences:  A227041 A227042 A227043 * A227045 A227046 A227047

KEYWORD

nonn

AUTHOR

Vaclav Kotesovec, Jun 29 2013

STATUS

approved

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Last modified February 26 05:19 EST 2020. Contains 332276 sequences. (Running on oeis4.)