

A185634


Number of nlength cycles from any point in a complete graph on n nodes.


1



1, 2, 21, 204, 2605, 39990, 720601, 14913080, 348678441, 9090909090, 261535698061, 8230246567620, 281241170407093, 10371206370520814, 410525522232055665, 17361641481138401520, 781282469559318055057, 37275544492386193492506, 1879498672877297909667781
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

2,2


COMMENTS

If M is the n X n matrix filled with ones, a(n) is the upper left element of (MId)^n


LINKS



FORMULA

a(n) = floor((n1)^n/n) + ((1)^n+1)/2
a(n) = floor((n1)^n/n)+1 for n odd, a(n) = floor((n1)^n/n) for n even.


EXAMPLE

In a complete graph in 5 nodes, there are 204 different cycles with a length of 5, from a point to itself.


CROSSREFS



KEYWORD

easy,nonn


AUTHOR



STATUS

approved



