# A216152 (b-file synthesized from sequence entry)
1 1
2 2
3 12
4 48
5 144
6 1440
7 34560
8 483840
9 7257600
10 58060800
11 3135283200
12 125411328000
13 2633637888000
14 57940033536000
15 5562243219456000
16 27811216097280000
17 723091618529280000
18 6507824566763520000
19 364438175738757120000
20 327994358164881408000000