Sum of the numerators for computing the third moment of the probability mass function for probability of k pairs among the involutions on n elements (A000085) assuming equal likelihood.
A174774
Sum of the numerators for computing the third moment of the probability mass function for probability of k pairs among the involutions on n elements (A000085) assuming equal likelihood.
Terms
- a(0) =0a(1) =1a(2) =3a(3) =30a(4) =130a(5) =780a(6) =3696a(7) =19768a(8) =97560a(9) =510660a(10) =2603260a(11) =13754136a(12) =72333768a(13) =390339040a(14) =2116922640a(15) =11722194240a(16) =65521880896a(17) =372897624528
External references
- oeis: A174774