A160967 Numbers of the form (4^k - 1)/3 or 2^k.

0, 1, 2, 4, 5, 8, 16, 21, 32, 64, 85, 128, 256, 341, 512, 1024, 1365, 2048, 4096, 5461, 8192, 16384, 21845, 32768, 65536, 87381, 131072, 262144, 349525, 524288, 1048576, 1398101, 2097152, 4194304, 5592405, 8388608, 16777216, 22369621, 33554432