# A293494 (b-file synthesized from sequence entry)
0 1
1 0
2 2
3 0
4 12
5 120
6 120
7 5040
8 42000
9 181440
10 5473440
11 46569600
12 479666880
13 12713500800
14 123519876480
15 2190354566400
16 54922842374400
17 652587628492800
18 16192687807296000
19 400439258111692800
20 5994400896144460800
21 182793304684134144000
22 4590673238662192281600