Number of 3Xn integer arrays with each element equal to the number of horizontal, diagonal and antidiagonal neighbors exactly one smaller than itself.

A266133

Number of 3Xn integer arrays with each element equal to the number of horizontal, diagonal and antidiagonal neighbors exactly one smaller than itself.

Terms

    a(0) =1a(1) =20a(2) =77a(3) =117a(4) =278a(5) =1959a(6) =11044a(7) =36730a(8) =123887a(9) =598383a(10) =2919993a(11) =11429093a(12) =43919671a(13) =194434626a(14) =880889564a(15) =3627851352a(16) =14690154222a(17) =63196827262a(18) =276336307138

External references