Half the number of (n+2)X(n+2) binary arrays with each 3X3 subblock having sum 4 or 5.
A186816
Half the number of (n+2)X(n+2) binary arrays with each 3X3 subblock having sum 4 or 5.
Terms
- a(0) =126a(1) =3988a(2) =222632a(3) =24581099a(4) =5634207241
External references
- oeis: A186816