a(n) is the number of n-digit numbers that contain '22' in their decimal representation.

A365137

a(n) is the number of n-digit numbers that contain '22' in their decimal representation.

Terms

    a(0) =0a(1) =0a(2) =1a(3) =18a(4) =261a(5) =3411a(6) =42048a(7) =499131a(8) =5770611a(9) =65427678a(10) =730784601a(11) =8065910511a(12) =88170256008a(13) =956125498671

External references