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A003017 Expansion of 1/(1 - x*exp(x) + x^2*exp(2*x) - x^3*exp(3*x)). 0
1, 1, 2, 3, 28, 605, 9366, 116767, 1310408, 15812505, 263924650, 6018875291, 148630870092, 3548481410773, 82543469312318, 2000101425252855, 54347539111582096, 1678367049470539697, 56020955060945897298 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
Vladimir Kruchinin and D. V. Kruchinin, Composita and their properties , arXiv:1103.2582 [math.CO], 2011-2013.
FORMULA
a(n) = sum(sum(k^(n-k)/(n-k)!*sum(binomial(j,k-3*m+2*j)*(-1)^(k-3*m+2*j)*binomial(m,j),j,0,m),k,m,n),m,1,n), n>0. - Vladimir Kruchinin, Aug 20 2010
PROG
(Maxima) a(n):=sum(sum(k^(n-k)/(n-k)!*sum(binomial(j, k-3*m+2*j)*(-1)^(k-3*m+2*j)*binomial(m, j), j, 0, m), k, m, n), m, 1, n); /* Vladimir Kruchinin, Aug 20 2010 */
CROSSREFS
Sequence in context: A219975 A319146 A206591 * A096580 A371024 A351693
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified May 21 13:22 EDT 2024. Contains 372736 sequences. (Running on oeis4.)