a(n) is the concatenation of first n terms of A033307.

A252043

a(n) is the concatenation of first n terms of A033307.

Terms

    a(0) =1a(1) =12a(2) =123a(3) =1234a(4) =12345a(5) =123456a(6) =1234567a(7) =12345678a(8) =123456789a(9) =1234567891a(10) =12345678910a(11) =123456789101

External references