# A081050 (b-file synthesized from sequence entry)
0 1
1 0
2 5
3 5
4 74
5 154
6 2484
7 8028
8 149904
9 663696
10 14257440
11 80627040
12 1965444480
13 13575738240
14 370643938560
15 3031488633600
16 91657072281600
17 867718162483200
18 28779361764249600
19 309920046408806400
20 11185850044938240000