# A227545 (b-file synthesized from sequence entry)
0 1
1 1
2 2
3 10
4 40
5 296
6 1936
7 17872
8 164480
9 1820800
10 21442816
11 279255296
12 3967316992
13 59837670400
14 988024924160
15 17009993230336
16 318566665977856
17 6177885274406912
18 129053377688043520
19 2786107670662021120
20 64136976817284448256
21 1525720008470138454016
22 38350749144768938770432