# A200319 (b-file synthesized from sequence entry) 1 1 2 2 3 12 4 132 5 2040 6 40440 7 979440 8 28034160 9 925858080 10 34654465440 11 1449705660480 12 67029745527360 13 3394417068282240 14 186842736763562880 15 11107390768144070400 16 709223357051739129600 17 48408150749346010022400 18 3517279496138031162739200 19 271050342684747077612160000