A293044 - cp's OEIS frontend

A293044 Number of even permutations s of {1,2,...,n} such that |s(i)-i| > 1 for each i=1,2,...,n.

n	a(n)
0	1
1	0
2	0
3	0
4	1
5	2
6	14
7	104
8	854
9	7850
10	79870
11	890348
12	10799871
13	141647372
14	1997815108
15	30156348224
16	485117044079
17	8285798537070
18	149759338727580
19	2855791585334780
20	57300933786123530
21	1206811729692494146
22	26619251746350630604
23	613691499376088985144

[1, 0, 0, 0, 1, 2, 14, 104, 854, 7850, 79870, 890348, 10799871, 141647372, 1997815108, 30156348224, 485117044079, 8285798537070, 149759338727580, 2855791585334780, 57300933786123530, 1206811729692494146, 26619251746350630604, 613691499376088985144]

cp's OEIS Frontend

A293044 Number of even permutations s of {1,2,...,n} such that |s(i)-i| > 1 for each i=1,2,...,n.

Table of values

List of values