A033285 n-th number whose maximal base 10 run length is 4.

1111, 2222, 3333, 4444, 5555, 6666, 7777, 8888, 9999, 10000, 11110, 11112, 11113, 11114, 11115, 11116, 11117, 11118, 11119, 12222, 13333, 14444, 15555, 16666, 17777, 18888, 19999, 20000, 21111, 22220, 22221, 22223