# A003287 (b-file synthesized from sequence entry) 1 1 2 4 3 22 4 140 5 970 6 7196 7 56092 8 452064 9 3735700 10 31484244 11 269613896 12 2339571468 13 20529434520 14 181871459580 15 1624587752400 16 14617165101216