A151881 - cp's OEIS frontend

A151881 Sum (number of cycles)^2 over all n! permutations of [1..n].

n	a(n)
1	1
2	5
3	23
4	120
5	724
6	5012
7	39332
8	345832
9	3371976
10	36135792
11	422379792
12	5349561984
13	72996193152
14	1067779243008
15	16670798231040
16	276718772067840
17	4866610479828480
18	90401487246167040
19	1768784607499944960
20	36360467544043008000
21	783508616506603008000

[1, 5, 23, 120, 724, 5012, 39332, 345832, 3371976, 36135792, 422379792, 5349561984, 72996193152, 1067779243008, 16670798231040, 276718772067840, 4866610479828480, 90401487246167040, 1768784607499944960, 36360467544043008000, 783508616506603008000]

cp's OEIS Frontend

A151881 Sum (number of cycles)^2 over all n! permutations of [1..n].

Table of values

List of values