Number of n-digit decimal numbers containing 123 as a substring.

A328916

Number of n-digit decimal numbers containing 123 as a substring.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =1a(4) =19a(5) =280a(6) =3699a(7) =45971a(8) =549430a(9) =6390601a(10) =72860039a(11) =818050960a(12) =9074118999a(13) =99668329951

External references