# A344065 (b-file synthesized from sequence entry) 0 1 1 1 2 6 3 42 4 252 5 1728 6 10584 7 71280 8 435456 9 2939328 10 17962560 11 119532672 12 739031040 13 4867527168 14 30051689472 15 198147658752 16 1221537687552 17 7984437608448 18 49643697954816 19 321998350270464 20 1997815999463424 21 12977575759282176 22 80455233450737664 23 519208351807832064