Number of (n+2)X(3+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000101 00010101 or 01010101.

A260010

Number of (n+2)X(3+2) 0..1 arrays with each 3X3 subblock having clockwise perimeter pattern 00000101 00010101 or 01010101.

Terms

    a(0) =109a(1) =252a(2) =889a(3) =2492a(4) =6944a(5) =18356a(6) =56137a(7) =155304a(8) =457083a(9) =1237656a(10) =3708013a(11) =10156868a(12) =30171658a(13) =82173696a(14) =245127382a(15) =669551372a(16) =1993152025a(17) =5436308892a(18) =16199822928a(19) =44216960412a(20) =131695381211a(21) =359328558160

External references