# A211195 (b-file synthesized from sequence entry) 0 1 1 2 2 6 3 32 4 240 5 2232 6 24080 7 290048 8 3809088 9 53691840 10 803569184 11 12670027776 12 209244552192 13 3603569846912 14 64493380379520 15 1196207964360704 16 22942371004144640 17 454160262238341120 18 9265017815023565312 19 194524772488764702720 20 4198521645139971459072