# A001568 (b-file synthesized from sequence entry)
1 1
2 -1
3 -1
4 2
5 49
6 629
7 6961
8 38366
9 -1899687
10 -133065253
11 -6482111309
12 -281940658286
13 -10702380933551
14 -247708227641863
15 14512103549430397
16 3377044611825908414
17 433180638973276282801
18 47474992085447610990231