# A006223 (b-file synthesized from sequence entry) 7 1 8 14 9 118 10 780 11 4466 12 23276 13 113620 14 528840 15 2375100 16 10378056 17 44381832 18 186574864 19 773564328 20 3171317360 21 12880883408 22 51915526432 23 207893871472 24 827983736608