# A009506 (b-file synthesized from sequence entry)
0 1
1 4
2 12
3 -296
4 -25200
5 -1885952
6 -163728576
7 -16916558720
8 -2050105730816
9 -282656394482688
10 -42100913802486784
11 -6025333851231979520
12 -461235714949468024832
13 265243699159867430764544