# A013265 (b-file synthesized from sequence entry)
0 0
1 0
2 -1
3 1
4 -6
5 23
6 -90
7 509
8 -1960
9 7251
10 27720
11 -1167421
12 20353608
13 -322757359
14 4828920096
15 -72221046535
16 1088176720800
17 -16527535024457
18 253611377594496
19 -3894220888850401
20 59159990565014280