# A012847 (b-file synthesized from sequence entry)
0 1
1 4
2 28
3 152
4 6928
5 2225408
6 348750400
7 38567316608
8 5024551512320
9 2238520490011648
10 1265695140964379648
11 555587429710072952832
12 218348017328527789264896
13 124784882666107086189330432