# A084240 (b-file synthesized from sequence entry)
0 1
1 0
2 -4
3 20
4 -84
5 340
6 -1364
7 5460
8 -21844
9 87380
10 -349524
11 1398100
12 -5592404
13 22369620
14 -89478484
15 357913940
16 -1431655764
17 5726623060
18 -22906492244
19 91625968980
20 -366503875924
21 1466015503700
22 -5864062014804
23 23456248059220
24 -93824992236884
25 375299968947540