A106000 Keep only the first digit of each integer and concatenate them. The result is the concatenation of all integers of the sequence.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 111, 211, 1111, 1112, 1113, 2111, 11111, 11112, 11113, 11114, 11115, 11116, 11117, 11118, 11119, 21111, 111111, 111112, 111113, 311111, 2111111, 11111111, 11111112, 11111113, 11111114, 11111115, 11111116