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A003723
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E.g.f. exp(tanh(x)).
(Formerly M4327)
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4
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1, 1, 1, -1, -7, -3, 97, 275, -2063, -15015, 53409, 968167, -752343, -77000363, -166831871, 7433044411, 43685848289, -843598411471, -9398558916159, 107426835190735, 2116926930779225, -14072980460605907
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,5
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COMMENTS
| Row sums of triangle A111593.
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REFERENCES
| N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
| T. D. Noe, Table of n, a(n) for n=0..100
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FORMULA
| a(n):=sum(m=1..n, sum(k=m..n, binomial(k-1,m-1)*k!*(-1)^(m+k)*2^(n-k)*stirling2(n,k))/m!), n>0, a(0)=1. [From Vladimir Kruchinin, Jun 28 2011 ]
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PROG
| (Maxima)
a(n):=if n=0 then 1 else sum(sum(binomial(k-1, m-1)*k!*(-1)^(m+k)*2^(n-k)*stirling2(n, k), k, m, n)/m!, m, 1, n); [From Vladimir Kruchinin, Jun 28 2011 ]
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CROSSREFS
| Cf. A003706, A003710.
Sequence in context: A176328 A183421 A173443 * A054471 A086453 A112099
Adjacent sequences: A003720 A003721 A003722 * A003724 A003725 A003726
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KEYWORD
| sign
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AUTHOR
| R. H. Hardin (rhhardin(AT)att.net), Simon Plouffe (simon.plouffe(AT)gmail.com)
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