# A012051 (b-file synthesized from sequence entry) 0 1 1 1 2 1 3 2 4 5 5 16 6 61 7 216 8 937 9 -1280 10 -34919 11 -1141504 12 -13257619 13 -263392128 14 -3269873515 15 -64804059904 16 -890367567919 17 -18858549039104 18 -286428853272143 19 -6592583427379200 20 -109915623105978539