A044173 Numbers n such that string 5,0 occurs in the base 7 representation of n but not of n-1.

35, 84, 133, 182, 231, 245, 280, 329, 378, 427, 476, 525, 574, 588, 623, 672, 721, 770, 819, 868, 917, 931, 966, 1015, 1064, 1113, 1162, 1211, 1260, 1274, 1309, 1358, 1407, 1456, 1505, 1554, 1603, 1617, 1652, 1701, 1715, 1799