Number of nX4 0..1 arrays with every element unequal to 0, 1, 2 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

A318339

Number of nX4 0..1 arrays with every element unequal to 0, 1, 2 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =8a(1) =20a(2) =36a(3) =67a(4) =148a(5) =343a(6) =817a(7) =1975a(8) =4788a(9) =11644a(10) =28327a(11) =68949a(12) =167840a(13) =408591a(14) =994711a(15) =2421617a(16) =5895464a(17) =14352589a(18) =34941627a(19) =85066013a(20) =207094729a(21) =504175889a(22) =1227425339a(23) =2988189330a(24) =7274801283a(25) =17710636103a(26) =43116865936a(27) =104968794797

External references