# A005401 (b-file synthesized from sequence entry)
1 4
2 16
3 64
4 416
5 4544
6 23488
7 -207616
8 4205056
9 198295552
10 -2574439424
11 -112886362112
12 3567419838464
13 94446596145152
14 -5636771173998592
15 -80736001427931136
16 11035864514607054848
17 15012780903941799936
18 -25650368909583695740928