Number of length-n 0..3 arrays with no repeated value differing from the previous repeated value by one.

A269489

Number of length-n 0..3 arrays with no repeated value differing from the previous repeated value by one.

Terms

    a(0) =4a(1) =16a(2) =64a(3) =250a(4) =964a(5) =3680a(6) =13946a(7) =52562a(8) =197288a(9) =738190a(10) =2755492a(11) =10266910a(12) =38201266a(13) =141989786a(14) =527337242a(15) =1957297844a(16) =7261528508a(17) =26930981728a(18) =99854569606a(19) =370173077224

External references