# A081670 (b-file synthesized from sequence entry) 0 1 1 4 2 14 3 46 4 150 5 494 6 1652 7 5618 8 19430 9 68302 10 243804 11 882578 12 3235596 13 11994922 14 44899568 15 169466426 16 644127110 17 2462746382 18 9462555788 19 36507525266 20 141333313220 21 548718227642 22 2135480023328 23 8327573906426 24 32530033219580