# A009148 (b-file synthesized from sequence entry) 0 1 1 0 2 0 3 0 4 12 5 -60 6 210 7 -1260 8 11760 9 -114912 10 1111560 11 -11676720 12 138570696 13 -1799232864 14 25005472128 15 -371229549600 16 5885388887040 17 -99270313446784 18 1773606197591232 19 -33452898176207232 20 664355584657373312