# A006606 (b-file synthesized from sequence entry) 1 1 2 2 3 3 4 6 5 10 6 20 7 36 8 72 9 135 10 272 11 528 12 1048 13 2080 14 4160 15 8242 16 16500 17 32895 18 65750 19 131328 20 262612 21 524733 22 1049600 23 2098176 24 4195930 25 8390620 26 16781312 27 33558177 28 67116876 29 134225920 30 268450626 31 536887270