# A127517 (b-file synthesized from sequence entry) 1 1 2 2 3 6 4 30 5 60 6 420 7 840 8 280 9 2520 10 2520 11 2520 12 27720 13 27720 14 27720 15 471240 16 942480 17 314160 18 9110640 19 9110640 20 1822128 21 41908944 22 209544720 23 2724081360 24 908027120 25 17252515280 26 17252515280 27 17252515280 28 17252515280 29 465817912560