Number of (n+1) X 2 0..2 arrays with every 2 X 2 subblock commuting with each of its horizontal and vertical 2 X 2 subblock neighbors.

A186464

Number of (n+1) X 2 0..2 arrays with every 2 X 2 subblock commuting with each of its horizontal and vertical 2 X 2 subblock neighbors.

Terms

    a(0) =81a(1) =83a(2) =277a(3) =367a(4) =966a(5) =1321a(6) =3078a(7) =4553a(8) =10028a(9) =15650a(10) =32786a(11) =53166a(12) =107524a(13) =179614a(14) =353932a(15) =604474a(16) =1168188a(17) =2028530a(18) =3863852a(19) =6793514a(20) =12800564a(21) =22716978a(22) =42458812a(23) =75878698a(24) =140963524a(25) =253237282a(26) =468324588a(27) =844629530a(28) =1556731220

External references