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 A009777 E.g.f. tanh(log(1+x))*cosh(x). 0
 0, 1, -1, 3, 0, -25, 165, -623, 392, 18909, -206685, 1233551, -1161336, -81119597, 1241356025, -10102782675, 12681799920, 1158387845177, -22791296600793, 234950313889819, -368659923645520, -41597707520306049 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS Table of n, a(n) for n=0..21. FORMULA a(n)=(sum(i=0..(n-1)/2, binomial(n,2*i)*(sum(m=1..n-2*i, (sum(k=1..m, (-1)^(k+1)*k!*2^(m-k)*stirling2(m,k)))*stirling1(n-2*i,m))))). - Vladimir Kruchinin, Jun 29 2011 PROG (Maxima) a(n):=(sum(binomial(n, 2*i)*(sum((sum((-1)^(k+1)*k!*2^(m-k)*stirling2(m, k), k, 1, m))*stirling1(n-2*i, m), m, 1, n-2*i)), i, 0, (n-1)/2)); /* Vladimir Kruchinin, Jun 29 2011 */ CROSSREFS Sequence in context: A344996 A057379 A360063 * A138543 A238104 A143769 Adjacent sequences: A009774 A009775 A009776 * A009778 A009779 A009780 KEYWORD sign,easy AUTHOR R. H. Hardin EXTENSIONS Extended with signs by Olivier Gérard, Mar 15 1997 STATUS approved

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Last modified September 22 14:10 EDT 2023. Contains 365531 sequences. (Running on oeis4.)