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Number of 7Xn binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.
1

%I #4 Feb 19 2016 08:49:44

%S 128,1760,43959,742688,14011359,236272677,4064720816,67174864630,

%T 1109043586715,17995383255288,290431722641261,4645047826683577,

%U 73887191299532384,1168678595574438796,18400291710723401503

%N Number of 7Xn binary arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two not more than once.

%C Row 7 of A269075.

%H R. H. Hardin, <a href="/A269081/b269081.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=3

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

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

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

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

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

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

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

%Y Cf. A269075.

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 19 2016