A044395 Numbers n such that string 6,3 occurs in the base 10 representation of n but not of n-1.

63, 163, 263, 363, 463, 563, 630, 663, 763, 863, 963, 1063, 1163, 1263, 1363, 1463, 1563, 1630, 1663, 1763, 1863, 1963, 2063, 2163, 2263, 2363, 2463, 2563, 2630, 2663, 2763, 2863, 2963, 3063, 3163, 3263, 3363, 3463, 3563