# A074360 (b-file synthesized from sequence entry) 0 0 1 0 2 0 3 0 4 0 5 40 6 232 7 1072 8 4400 9 16864 10 61728 11 218496 12 753792 13 2547840 14 8468608 15 27755776 16 89886976 17 288101888 18 915089920 19 2883416064 20 9021001728 21 28042881024 22 86672025600 23 266472878080 24 815347462144 25 2483820617728