Number of 1 X n 0..3 arrays avoiding the pattern z-2 z-1 z in any row, column, nw-to-se diagonal or ne-to-sw antidiagonal.

A206839

Number of 1 X n 0..3 arrays avoiding the pattern z-2 z-1 z in any row, column, nw-to-se diagonal or ne-to-sw antidiagonal.

Terms

    a(0) =1a(1) =4a(2) =16a(3) =62a(4) =241a(5) =936a(6) =3636a(7) =14124a(8) =54865a(9) =213124a(10) =827884a(11) =3215930a(12) =12492337a(13) =48526704a(14) =188502840a(15) =732242616a(16) =2844409393a(17) =11049158596a(18) =42920651992a(19) =166726031798a(20) =647650219393

External references