A033019 Numbers n such that every run of digits of n in base 6 has length >=2.

7, 14, 21, 28, 35, 43, 86, 129, 172, 215, 252, 259, 266, 273, 280, 287, 504, 511, 518, 525, 532, 539, 756, 763, 770, 777, 784, 791, 1008, 1015, 1022, 1029, 1036, 1043, 1260, 1267, 1274, 1281, 1288, 1295, 1512, 1548, 1555, 1562