Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000011 or 00001111.

A260363

Number of (n+2) X (1+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000011 or 00001111.

Terms

    a(0) =48a(1) =78a(2) =208a(3) =436a(4) =616a(5) =1378a(6) =2880a(7) =4904a(8) =9776a(9) =19458a(10) =35928a(11) =70096a(12) =136184a(13) =257558a(14) =498984a(15) =963740a(16) =1839600a(17) =3547926a(18) =6837184a(19) =13109580a(20) =25236616a(21) =48572826a(22) =93304016a(23) =179507232a(24) =345319152a(25) =663776330a(26) =1276734024a(27) =2455611208a(28) =4721490968

External references