# A149238 (b-file synthesized from sequence entry) 0 1 1 1 2 4 3 11 4 36 5 125 6 435 7 1595 8 5954 9 22465 10 86223 11 334795 12 1315848 13 5206019 14 20773532 15 83318857 16 336730400 17 1367649633 18 5578371219 19 22851417683 20 93958046678 21 387906668755 22 1606184507258 23 6669799558525 24 27769835689296 25 115931233180053 26 485172793681327 27 2034581806716141 28 8549095477414610