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A001342
E.g.f.: 24*exp(x)/(1-x)^5.
(Formerly M5147 N2233)
3
24, 144, 984, 7584, 65304, 622704, 6523224, 74542464, 923389464, 12331112784, 176656186584, 2703187857504, 44010975525144, 759759305162544, 13863284116261464, 266629052052953664, 5391260831368104984, 114341673457251051024, 2538207055383516388824
OFFSET
0,1
REFERENCES
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).
LINKS
E. Biondi, L. Divieti, and G. Guardabassi, Counting paths, circuits, chains and cycles in graphs: A unified approach, Canad. J. Math. 22 1970 22-35.
FORMULA
a(n) = floor( n! * (n^4+6*n^3+17*n^2+20*n+9) * exp(1) ). [Mark van Hoeij, Nov 11 2009]
a(n) = Sum_{k=0..n} binomial(n, k)*(k+4)!. - Christian Krause, Dec 21 2022
MATHEMATICA
nn = 20; Range[0, nn]! CoefficientList[Series[24*Exp[x]/(1 - x)^5, {x, 0, nn}], x] (* T. D. Noe, Jun 28 2012 *)
PROG
(PARI) a(n) = n!*polcoeff(24*exp(x+x*O(x^n))/(1-x)^5, n) \\ Christian Krause, Dec 21 2022
CROSSREFS
Same as 24*A095177.
Sequence in context: A182075 A054118 A223373 * A029572 A129923 A064138
KEYWORD
nonn
EXTENSIONS
Error in description corrected Jan 30 2008
More terms from N. J. A. Sloane, Jan 30 2008
STATUS
approved