# A375808 (b-file synthesized from sequence entry)
0 1
1 2
2 6
3 24
4 144
5 1080
6 9360
7 94080
8 1078560
9 13789440
10 194745600
11 3013718400
12 50654419200
13 918900702720
14 17896250211840
15 372338481715200
16 8241399758592000
17 193366506222489600
18 4793430516921446400
19 125181207625240166400
20 3435031723216084992000