Number of 2Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 3 or 4 neighboring 1s.

A297750

Number of 2Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 3 or 4 neighboring 1s.

Terms

    a(0) =1a(1) =5a(2) =19a(3) =37a(4) =71a(5) =237a(6) =715a(7) =1665a(8) =4007a(9) =11381a(10) =31243a(11) =78473a(12) =200815a(13) =541613a(14) =1441299a(15) =3724657a(16) =9704567a(17) =25715349a(18) =67778555a(19) =176954073a(20) =463516063a(21) =1220730621a(22) =3208289763a(23) =8406208129a(24) =22053755335a(25) =57958276581a(26) =152196865739a(27) =399275986857

External references