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Number of n X n binary arrays with top left element equal to 1 and no two ones adjacent horizontally or nw-se.
1

%I #10 Dec 18 2015 18:18:39

%S 1,2,36,586,37944,3835792,1104367784,619684261316,861640042953968,

%T 2553753667566404176,17730379458709838261420,

%U 271886420146092794204826516,9552041362065797908250895398960,751574042423604397352344101718881740

%N Number of n X n binary arrays with top left element equal to 1 and no two ones adjacent horizontally or nw-se.

%C Diagonal of A228796

%H R. H. Hardin, <a href="/A228790/b228790.txt">Table of n, a(n) for n = 1..29</a>

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_ Sep 04 2013