login
Half the number of n X n symmetric binary matrices with no element unequal to a strict majority of its king-move neighbors
0

%I #5 Dec 18 2015 18:17:39

%S 1,1,1,2,5,20,86,486,3495,31938,368832,5412981,100924470,2390092072,

%T 71686035608,2726514241955,131508854502755,8039052200861454,

%U 622678408143680652

%N Half the number of n X n symmetric binary matrices with no element unequal to a strict majority of its king-move neighbors

%e Some solutions for n=5 with a(1,1)=0

%e ..0..0..1..1..1....0..0..0..1..1....0..0..0..1..1....0..0..0..0..0

%e ..0..0..1..1..1....0..0..0..1..1....0..0..0..1..1....0..0..0..0..0

%e ..1..1..0..0..0....0..0..1..1..1....0..0..0..1..1....0..0..0..0..0

%e ..1..1..0..0..0....1..1..1..1..1....1..1..1..0..0....0..0..0..0..0

%e ..1..1..0..0..0....1..1..1..1..1....1..1..1..0..0....0..0..0..0..0

%K nonn

%O 1,4

%A _R. H. Hardin_ May 16 2011