A138772 - cp's OEIS frontend

A138772 Number of entries in the second cycles of all permutations of {1,2,...,n}; each cycle is written with the smallest element first and cycles are arranged in increasing order of their first elements.

n	a(n)
1	0
2	1
3	5
4	27
5	168
6	1200
7	9720
8	88200
9	887040
10	9797760
11	117936000
12	1536796800
13	21555072000
14	323805081600
15	5187108326400
16	88268019840000
17	1590132031488000
18	30233431388160000
19	605024315191296000
20	12711912992722944000
21	279783730940313600000
22	6437458713635389440000

[0, 1, 5, 27, 168, 1200, 9720, 88200, 887040, 9797760, 117936000, 1536796800, 21555072000, 323805081600, 5187108326400, 88268019840000, 1590132031488000, 30233431388160000, 605024315191296000, 12711912992722944000, 279783730940313600000, 6437458713635389440000]

cp's OEIS Frontend

A138772 Number of entries in the second cycles of all permutations of {1,2,...,n}; each cycle is written with the smallest element first and cycles are arranged in increasing order of their first elements.

Table of values

List of values