# A155558 (b-file synthesized from sequence entry)
0 1
1 1
2 6
3 138
4 10488
5 8280
6 2485656
7 1392696
8 1794643632
9 663449904
10 448448112
11 3910528474128
12 904634615952
13 375908525712
14 25621782562486656
15 3570752184568704
16 852504801992064
17 514242863174016
18 504057328351799983488