# A013278 (b-file synthesized from sequence entry) 0 0 1 0 2 -1 3 3 4 -6 5 15 6 -150 7 1575 8 -12600 9 101115 10 -1103760 11 14708925 12 -198336600 13 2783105325 14 -43768604880 15 754367488875 16 -13648397162400 17 262037979177975 18 -5424089927256000 19 118958487086664225