# A109591 (b-file synthesized from sequence entry) 0 0 1 -3 2 2 3 3 4 56 5 -360 6 12420 7 -303030 8 10226880 9 -381416040 10 16356484800 11 -781899663600 12 41374146038400 13 -2397894225620400 14 151087293619567200 15 -10281399143079546000 16 751437976013183232000 17 -58702720576973120928000 18 4881171236699697126048000