a(n) = 100*(10^n - 1)/9.

A124166

a(n) = 100*(10^n - 1)/9.

Terms

    a(0) =0a(1) =100a(2) =1100a(3) =11100a(4) =111100a(5) =1111100a(6) =11111100a(7) =111111100a(8) =1111111100a(9) =11111111100a(10) =111111111100

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