# A331733 (b-file synthesized from sequence entry) 1 1 2 3 3 7 4 4 5 31 6 15 7 511 8 12 9 13 10 63 11 131071 12 28 13 8589934591 14 1023 15 127 16 6 17 36893488147419103231 18 39 19 680564733841876926926749214863536422911 20 124 21 2047 22 262143 23 231584178474632390847141970017375815706539969331281128078915168015826259279871 24 60 25 121 26 17179869183 27 91 28 2044