# A144273 (b-file synthesized from sequence entry)
0 1
1 1
2 4
3 19
4 132
5 1119
6 12057
7 151560
8 2234970
9 37355130
10 702161460
11 14608747440
12 333760916475
13 8297318063475
14 223043540630400
15 6444290305953675
16 199158606533605950
17 6554872218153191625
18 228899544451085017125
19 8452452568601816775000
20 329069272855540304587500