# A072973 (b-file synthesized from sequence entry)
0 1
1 3
2 30
3 14
4 3960
5 24024
6 28288
7 1860480
8 94140288
9 199971200
10 1183311360
11 12386350080
12 284826214400
13 2376389615616
14 433030996623360
15 15188999733248
16 73886889202384896
17 484018391833804800
18 4234776786964971520