A044370 Numbers n such that string 3,8 occurs in the base 10 representation of n but not of n-1.

38, 138, 238, 338, 380, 438, 538, 638, 738, 838, 938, 1038, 1138, 1238, 1338, 1380, 1438, 1538, 1638, 1738, 1838, 1938, 2038, 2138, 2238, 2338, 2380, 2438, 2538, 2638, 2738, 2838, 2938, 3038, 3138, 3238, 3338, 3380, 3438