# A259459 (b-file synthesized from sequence entry)
0 1
1 18
2 360
3 9000
4 283500
5 11113200
6 533433600
7 30862944000
8 2121827400000
9 171160743600000
10 16020645600960000
11 1722947613266880000
12 211061082625192800000
13 29223842209642080000000
14 4542220046298654720000000