Number of nX4 0..1 arrays with every element unequal to 0, 2, 3 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

A318419

Number of nX4 0..1 arrays with every element unequal to 0, 2, 3 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Terms

    a(0) =1a(1) =3a(2) =4a(3) =18a(4) =71a(5) =126a(6) =225a(7) =691a(8) =2116a(9) =6101a(10) =15907a(11) =40782a(12) =110244a(13) =304223a(14) =831408a(15) =2242597a(16) =6029313a(17) =16289354a(18) =44168735a(19) =119711796a(20) =323891119a(21) =875720673a(22) =2368763705a(23) =6410688069a(24) =17350642443a(25) =46950362332a(26) =127030237584a(27) =343705347091

External references