# A048643 (b-file synthesized from sequence entry)
0 0
1 0
2 1
3 0
4 12
5 132
6 540
7 0
8 20160
9 423360
10 8164800
11 125193600
12 1172102400
13 11935123200
14 76281004800
15 0
16 10461394944000
17 428917192704000
18 14781951055872000
19 429147343392768000
20 14090871305871360000
21 461146030563778560000
22 13730871481551544320000
23 390084405122331279360000