# A149853 (b-file synthesized from sequence entry) 0 1 1 2 2 5 3 13 4 35 5 104 6 318 7 1014 8 3256 9 10543 10 34937 11 116848 12 397242 13 1354804 14 4641335 15 16053619 16 55784113 17 195466771 18 686258063 19 2416219435 20 8551265471 21 30349165784 22 108247450688 23 386615499598 24 1383536609787 25 4967118466568 26 17866856266359 27 64477119071662 28 232917119736270 29 842589117795023 30 3054850488851820