# A268349 (b-file synthesized from sequence entry) 0 1 1 2 2 3 3 4 4 20 5 45 6 109 7 275 8 708 9 1765 10 4442 11 11196 12 28207 13 70985 14 178755 15 450130 16 1133423 17 2853888 18 7186144 19 18094709 20 45562353 21 114725755 22 288879164 23 727396569 24 1831581574 25 4611915224 26 11612784735 27 29240946181 28 73628587619 29 185396495082