A044566 Numbers n such that string 6,5 occurs in the base 7 representation of n but not of n+1.

47, 96, 145, 194, 243, 292, 335, 341, 390, 439, 488, 537, 586, 635, 678, 684, 733, 782, 831, 880, 929, 978, 1021, 1027, 1076, 1125, 1174, 1223, 1272, 1321, 1364, 1370, 1419, 1468, 1517, 1566, 1615, 1664, 1707, 1713, 1762, 1811