Number of length-n 0..3 arrays with no repeated value differing from the previous repeated value by other than plus or minus one modulo 3+1.

A269673

Number of length-n 0..3 arrays with no repeated value differing from the previous repeated value by other than plus or minus one modulo 3+1.

Terms

    a(0) =4a(1) =16a(2) =60a(3) =224a(4) =820a(5) =2976a(6) =10700a(7) =38224a(8) =135780a(9) =480176a(10) =1691740a(11) =5941824a(12) =20814740a(13) =72755776a(14) =253836780a(15) =884207024a(16) =3075861700a(17) =10687549776a(18) =37098781820a(19) =128668433824a(20) =445930140660

External references