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 A191594 Expansion of (1-exp(x))/(1+x^2-exp(x))=sum(n>=0, a(n)*x^n/n!^2) 0
 1, 1, 2, 3, -48, -1220, -19440, -69720, 14407680, 953539776, 35565868800, -210727440000, -201519805132800, -23287596250913280, -1387143593335019520, 70361372381908608000, 36238719331572645888000, 6110545675513945739673600, 457510061917491552313344000, -86824257027562156263159398400, -44392403385021894430349721600000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA a(n)=n!^2*sum(m=1..n-1, (m!*sum(k=1..n-m, (k!*stirling1(m+k,m)*stirling2(n-m,k))/(m+k)!))/(n-m)!)+n!^2. PROG (Maxima) a(n):=n!^2*sum((m!*sum((k!*stirling1(m+k, m)*stirling2(n-m, k))/(m+k)!, k, 1, n-m))/(n-m)!, m, 1, n-1)+n!^2; CROSSREFS Sequence in context: A215536 A173355 A118222 * A208204 A067092 A041133 Adjacent sequences:  A191591 A191592 A191593 * A191595 A191596 A191597 KEYWORD sign AUTHOR Vladimir Kruchinin, Jun 07 2011 STATUS approved

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Last modified July 20 01:38 EDT 2019. Contains 325168 sequences. (Running on oeis4.)