# A049176 (b-file synthesized from sequence entry) 1 1 2 1 3 3 4 9 5 33 6 127 7 519 8 2189 9 9489 10 41953 11 188531 12 858441 13 3952133 14 18365543 15 86031567 16 405819137 17 1925991665 18 9189984561 19 44061194915 20 212159132049 21 1025525299369 22 4974525125023 23 24206966311287 24 118138984314029