# A334324 (b-file synthesized from sequence entry) 1 4 2 8 3 24 4 64 5 200 6 504 7 1400 8 3648 9 9720 10 25560 11 67936 12 178464 13 472576 14 1244208 15 3286080 16 8663232 17 22861600 18 60291504 19 159063744 20 419556560 21 1106794584 22 2919596768 23 7701735288 24 20316965760 25 53595401400 26 141384847344 27 372973574160 28 983911970608 29 2595592842456 30 6847273559040