# A000649 (b-file synthesized from sequence entry) 0 1 1 5 2 30 3 115 4 425 5 1396 6 4440 7 13470 8 40000 9 116140 10 332827 11 942435 12 2647450 13 7386925 14 20511620 15 56731383 16 156451985 17 430462915 18 1182341890 19 3243215495 20 8887664047 21 24338341165 22 66616422775 23 182276901760 24 498657609720 25 1364083988834