# A009544 (b-file synthesized from sequence entry)
0 0
1 1
2 2
3 2
4 -8
5 -44
6 8
7 944
8 2304
9 -27632
10 -183776
11 975072
12 15141248
13 -27882048
14 -1461427328
15 -1986004224
16 166452797440
17 850359527680
18 -21941424508416
19 -222801125934592
20 3231615038191616
21 57863671042155520