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A071007
Number of permutations in the symmetric group S_n such that the maximal cycle has length exactly 3.
2
0, 0, 0, 2, 8, 40, 200, 980, 5152, 28448, 162080, 979000, 6179360, 40575392, 279199648, 1997406320, 14825619200, 114365751040, 912510870272, 7521873125408, 64045101880960, 561615674345600, 5067769601121920, 47023128008540992, 447820056115824128
OFFSET
0,4
COMMENTS
E.g.f.: exp( x + (x^2)/2 + (x^3)/3 ) - exp( x + (x^2)/2 ).
LINKS
FORMULA
a(n) = A057693(n) - A000085(n).
MATHEMATICA
nn=20; Range[0, nn]!CoefficientList[Series[Exp[x+x^2/2+x^3/3]-Exp[x+x^2/2], {x, 0, nn}], x] (* Geoffrey Critzer, Jan 23 2013 *)
PROG
(PARI) for(n=0, 25, print1(polcoeff(serlaplace(exp(x+x^2/2+x^3/3)-exp(x+x^2/2)), n)", "))
CROSSREFS
Column k=3 of A126074.
Sequence in context: A231125 A221587 A186947 * A027617 A187071 A154626
KEYWORD
nonn
AUTHOR
Sharon Sela (sharonsela(AT)hotmail.com), May 19 2002
EXTENSIONS
More terms from Ralf Stephan, Apr 09 2003
STATUS
approved