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A001778 Lah numbers: n!C(n-1,5)/6!.
(Formerly M5279 N2297)
4
1, 42, 1176, 28224, 635040, 13970880, 307359360, 6849722880, 155831195520, 3636061228800, 87265469491200, 2157837063782400, 55024845126451200, 1447576694865100800, 39291367432052736000, 1100158288097476608000 (list; graph; refs; listen; history; internal format)
OFFSET

6,2

REFERENCES

L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 156.

J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 44.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

FORMULA

E.g.f.: ((x/(1-x))^6)/6!.

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)^n*f(n,6,-6), (n>=6). [From Milan R. Janjic (agnus(AT)blic.net), Mar 01 2009]

MATHEMATICA

With[{c=6!}, Table[n!Binomial[n-1, 5]/c, {n, 6, 24}]] (* From Harvey P. Dale, May 25 2011 *)

PROG

(Other) sage: [binomial(n, 6)*factorial (n-1)/factorial (5) for n in xrange(6, 22)] # [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jul 07 2009]

CROSSREFS

Column 6 of A008297.

Column m=6 of unsigned triangle A111596.

Sequence in context: A016094 A004361 A004373 * A111780 A075922 A077123

Adjacent sequences:  A001775 A001776 A001777 * A001779 A001780 A001781

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

EXTENSIONS

More terms from Christian G. Bower (bowerc(AT)usa.net), Dec 18 2001

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Last modified February 17 10:57 EST 2012. Contains 206009 sequences.