Number of n X 2 0..1 arrays with every nonzero element less than or equal to at least two horizontal and vertical neighbors.

A202973

Number of n X 2 0..1 arrays with every nonzero element less than or equal to at least two horizontal and vertical neighbors.

Terms

    a(0) =1a(1) =2a(2) =4a(3) =7a(4) =14a(5) =31a(6) =69a(7) =155a(8) =354a(9) =814a(10) =1875a(11) =4326a(12) =9993a(13) =23095a(14) =53387a(15) =123430a(16) =285394a(17) =659913a(18) =1525942a(19) =3528541a(20) =8159347a(21) =18867623a(22) =43629460a(23) =100888804a(24) =233295503a(25) =539473228a(26) =1247479743a(27) =2884676711a(28) =6670537293a(29) =15424975984

External references