A043890 Numbers n such that 1 and 2 occur juxtaposed in the base 5 representation of n but not of n+1.

7, 11, 32, 39, 59, 61, 82, 86, 107, 111, 132, 136, 157, 164, 199, 207, 211, 232, 236, 257, 261, 299, 309, 311, 332, 336, 357, 361, 382, 386, 407, 414, 434, 436, 457, 461, 482, 486, 507, 511, 532, 539, 559, 561, 582, 586, 607, 611