login
A239756
Number of pairs of functions (f,g) from a set of n elements into itself satisfying f(f(g(x))) = g(g(x)).
0
1, 1, 8, 129, 3616, 151845, 8864496, 682005919
OFFSET
0,3
CROSSREFS
Sequence in context: A364986 A338328 A073701 * A295240 A240630 A187609
KEYWORD
nonn,more
AUTHOR
Chad Brewbaker, Mar 26 2014
EXTENSIONS
a(6)-a(7) from Giovanni Resta, Mar 28 2014
STATUS
approved