A208661 - cp's OEIS frontend

A208661 Number of paths through the subset array of {1,2,...,n} that have range a subset of {1,2}; see Comments at A208650.

n	a(n)
1	1
2	4
3	16
4	144
5	3072
6	160000
7	20736000
8	6776582400
9	5639493386240
10	12041750911647744
11	66367674777600000000
12	948747002032456704000000
13	35319813420678024297185280000
14	3435829941215659552226769213849600

[1, 4, 16, 144, 3072, 160000, 20736000, 6776582400, 5639493386240, 12041750911647744, 66367674777600000000, 948747002032456704000000, 35319813420678024297185280000, 3435829941215659552226769213849600]

cp's OEIS Frontend

A208661 Number of paths through the subset array of {1,2,...,n} that have range a subset of {1,2}; see Comments at A208650.

Table of values

List of values