# A335595 (b-file synthesized from sequence entry)
0 1
1 0
2 0
3 4
4 12
5 48
6 400
7 3120
8 25872
9 251776
10 2715264
11 31809600
12 405296320
13 5580385536
14 82469607168
15 1302102360832
16 21875297337600
17 389590168842240
18 7331376554610688
19 145352459953603584
20 3028176414606560256
21 66135374473635328000
22 1510938930307368898560
23 36038691473858577444864