# A090228 (b-file synthesized from sequence entry) 0 0 1 1 2 8 3 168 4 714 5 1870 6 7920 7 54288 8 229970 9 602070 10 2550408 11 10803704 12 28284465 13 74049690 14 193864606 15 821223648 16 3478759200 17 9107509825 18 23843770274 19 62423800998 20 264431464440 21 1120149658760 22 2932589879121 23 7677619978602