%I #5 Dec 11 2020 09:57:42
%S 2,6,9,13,20,26,33,42,52,62
%N Maximum number of 1s in an nX(n+2) binary matrix with no three 1s adjacent in a line along a row, column or diagonally.
%e Some solutions for 6X8
%e ..0..1..1..0..1..0..1..1....0..1..1..0..1..0..1..1....0..1..1..0..1..0..1..1
%e ..1..0..0..1..1..0..0..1....1..1..0..1..1..0..0..1....1..1..0..1..0..1..1..0
%e ..0..1..0..1..0..1..1..0....0..0..0..1..0..1..1..0....0..0..0..1..0..0..0..1
%e ..1..1..0..0..0..0..0..1....1..1..0..0..0..0..0..1....0..1..1..0..1..0..1..0
%e ..1..0..1..1..0..1..1..0....1..0..1..1..0..1..1..0....1..0..0..1..1..0..1..1
%e ..0..1..1..0..1..0..1..1....0..1..1..0..1..0..1..1....1..1..0..1..0..1..0..1
%Y Superdiagonal 2 of A181019.
%K nonn,more
%O 1,1
%A _R. H. Hardin_, Sep 30 2010