A043883 Numbers n such that 1 and 2 occur juxtaposed in the base 4 representation of n but not of n+1.

6, 9, 22, 27, 39, 41, 54, 57, 70, 73, 86, 91, 111, 118, 121, 134, 137, 159, 167, 169, 182, 185, 198, 201, 214, 219, 231, 233, 246, 249, 262, 265, 278, 283, 295, 297, 310, 313, 326, 329, 342, 347, 367, 374, 377, 447, 454, 457, 470