# A354309 (b-file synthesized from sequence entry)
0 1
1 0
2 2
3 6
4 44
5 360
6 3744
7 46200
8 662864
9 10838016
10 198943200
11 4050937440
12 90613710912
13 2208677328000
14 58265734055424
15 1653914478303360
16 50263564166365440
17 1628300694034022400
18 56012708047907510784
19 2039053421375533094400
20 78314004507947110456320