# A206960 (b-file synthesized from sequence entry) 0 0 1 1 2 4 3 9 4 31 5 66 6 190 7 385 8 1022 9 2055 10 5112 11 10242 12 24572 13 49153 14 114686 15 229377 16 524287 17 1048590 18 2359281 19 4718599 20 10485753 21 20971521 22 46137342 23 92274689 24 201326590 25 402653191 26 872415224 27 1744830466 28 3758096380 29 7516192769 30 16106127358 31 32212254721