%I #14 Dec 31 2012 10:05:59
%S 1,2,21,204,2605,39990,720601,14913080,348678441,9090909090,
%T 261535698061,8230246567620,281241170407093,10371206370520814,
%U 410525522232055665,17361641481138401520,781282469559318055057,37275544492386193492506,1879498672877297909667781
%N Number of nlength cycles from any point in a complete graph on n nodes.
%C If M is the n X n matrix filled with ones, a(n) is the upper left element of (MId)^n
%F a(n) = floor((n1)^n/n) + ((1)^n+1)/2
%F a(n) = floor((n1)^n/n)+1 for n odd, a(n) = floor((n1)^n/n) for n even.
%e In a complete graph in 5 nodes, there are 204 different cycles with a length of 5, from a point to itself.
%Y Cf. A173499.
%K easy,nonn
%O 2,2
%A _Sébastien Dumortier_, Dec 18 2012
