# A212073 (b-file synthesized from sequence entry) 0 1 1 4 2 30 3 280 4 2925 5 32736 6 383838 7 4654320 8 57887550 9 734405100 10 9467075926 11 123648163392 12 1632743088275 13 21761329287600 14 292362576381900 15 3955219615609056 16 53834425161872586 17 736687428853685400 18 10129401435828605700 19 139876690363085200200