Number of inequivalent strings of 2n digits, when 2 strings are equivalent if turning 1 upside down gives the other.

A036257

Number of inequivalent strings of 2n digits, when 2 strings are equivalent if turning 1 upside down gives the other.

Terms

    a(0) =1a(1) =90a(2) =9700a(3) =992250a(4) =99805000a(5) =9995118750a(6) =999877937500

External references