# A111663 (b-file synthesized from sequence entry) 0 1 1 2 2 4 3 8 4 16 5 32 6 62 7 124 8 248 9 494 10 988 11 1976 12 3952 13 7904 14 15808 15 31616 16 63232 17 126464 18 252926 19 505852 20 1011704 21 2023406 22 4046812 23 8093624 24 16187248 25 32374496 26 64748992 27 129497984 28 258995968 29 517991936 30 1035983870 31 2071967740