A226349 - cp's OEIS frontend

A226349 Number of functions f:{1,2,...,n} -> {1,2,...,n} such that the 1 and the 2 are in the same component of the functional digraph representation of f.

n	a(n)
0	0
1	0
2	3
3	20
4	188
5	2280
6	33864
7	595196
8	12081600
9	278122032
10	7159299200
11	203771364324
12	6354217539072
13	215429796291320
14	7889813961243648
15	310413633428119500
16	13057068314325008384
17	584737112800511959104
18	27776659696045110558720
19	1395009275793285886030772
20	73854320834079368232960000

[0, 0, 3, 20, 188, 2280, 33864, 595196, 12081600, 278122032, 7159299200, 203771364324, 6354217539072, 215429796291320, 7889813961243648, 310413633428119500, 13057068314325008384, 584737112800511959104, 27776659696045110558720, 1395009275793285886030772, 73854320834079368232960000]

cp's OEIS Frontend

A226349 Number of functions f:{1,2,...,n} -> {1,2,...,n} such that the 1 and the 2 are in the same component of the functional digraph representation of f.

Table of values

List of values