A189566 - cp's OEIS frontend

A189566 Number of permutations p of 1,2,...,n satisfying |p(i+2)-p(i)|<>4 and |p(j+4)-p(j)|<>2 for all i=1..n-2, j=1..n-4.

n	a(n)
1	1
2	2
3	6
4	24
5	60
6	208
7	1184
8	7840
9	51636
10	410272
11	3836456
12	39971896
13	455888312
14	5717233896
15	78164908748
16	1153568477544
17	18263732340736
18	308795344195456
19	5550690255143992
20	105653899427070440
21	2122307518838927952

[1, 2, 6, 24, 60, 208, 1184, 7840, 51636, 410272, 3836456, 39971896, 455888312, 5717233896, 78164908748, 1153568477544, 18263732340736, 308795344195456, 5550690255143992, 105653899427070440, 2122307518838927952]

cp's OEIS Frontend

A189566 Number of permutations p of 1,2,...,n satisfying |p(i+2)-p(i)|<>4 and |p(j+4)-p(j)|<>2 for all i=1..n-2, j=1..n-4.

Table of values

List of values