# A163124 (b-file synthesized from sequence entry) 0 1 1 20 2 380 3 7220 4 136990 5 2599200 6 49316400 7 935712000 8 17753871510 9 336855735180 10 6391382632020 11 121267853544780 12 2300893742387430 13 43656351283440360 14 828320305398630840 15 15716259104684097960