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Search: id:A111597
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| A111597 |
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Lah numbers: n!*binomial(n-1,6)/7!. |
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+0
3
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| 1, 56, 2016, 60480, 1663200, 43908480, 1141620480, 29682132480, 779155977600, 20777492736000, 565147802419200, 15721384321843200, 448059453172531200, 13097122477350912000, 392913674320527360000, 12101741169072242688000
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OFFSET
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7,2
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REFERENCES
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L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 156.
J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 44.
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FORMULA
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E.g.f. ((x/(1-x))^7)/7!.
a(n)= (n!/7!)*binomial(n-1, 7-1).
If we define f(n,i,x)= sum(sum(binomial(k,j)*stirling1(n,k)*stirling2(j,i)*x^(k-j),j=i..k),k=i..n) then a(n+1)=(-1)^n*f(n,6,-8), (n>=6). [From Milan R. Janjic (agnus(AT)blic.net), Mar 01 2009]
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CROSSREFS
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Column 7 of A008297 and unsigned A111596. Column 6: A001778.
Sequence in context: A004375 A103726 A004387 this_sequence A111781 A124101 A003696
Adjacent sequences: A111594 A111595 A111596 this_sequence A111598 A111599 A111600
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KEYWORD
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nonn,easy
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AUTHOR
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Wolfdieter Lang (wolfdieter.lang_AT_physik_DOT_uni-karlsruhe_DOT_de), Aug 23 2005
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