# A091097 (b-file synthesized from sequence entry)
0 1
1 6
2 -24
3 216
4 -864
5 7776
6 -31104
7 279936
8 -1119744
9 10077696
10 -40310784
11 362797056
12 -1451188224
13 13060694016
14 -52242776064
15 470184984576
16 -1880739938304
17 16926659444736
18 -67706637778944
19 609359740010496
20 -2437438960041984