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%I #16 Oct 11 2017 20:43:16
%S 0,0,0,0,0,0,0,720,5760,51840,518400,5702400,68428800,889574400,
%T 11564467200,173467008000,2775472128000,47183026176000,
%U 849294471168000,16136594952192000,322731899043840000,6802195410616320000,149648299033559040000,3441910877771857920000
%N Number of permutations of an n-set containing a 7-cycle.
%H Alois P. Heinz, <a href="/A029574/b029574.txt">Table of n, a(n) for n = 0..450</a>
%F a(n) = n! * (1 - sum_{k=0..floor(n/7)} (-1)^k/(k!*7^k)).
%F a(n)/n! is asymptotic to 1-e^(-1/7) = 1 - A092750.
%F E.g.f.: (1-exp(-x^7/7))/(1-x). - _Alois P. Heinz_, Oct 11 2017
%o (PARI) a(n) = n! * (1 - sum(k=0, floor(n/7), (-1)^k/(k!*7^k) ) ); \\ _Michel Marcus_, Aug 08 2013
%Y Column k=7 of A293211.
%K nonn
%O 0,8
%A _Rob Pratt_
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