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%I #4 Feb 16 2016 13:58:29
%S 2187,184320,5598720,167226768,4823705520,137497776840,3870355944960,
%T 107884943899488,2981278225929744,81772049776604472,
%U 2228316762081730176,60378377050028640600,1627890867639031100112,43698886755490031302440
%N Number of 7Xn 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two not more than once.
%C Row 7 of A268971.
%H R. H. Hardin, <a href="/A268977/b268977.txt">Table of n, a(n) for n = 1..210</a>
%H R. H. Hardin, <a href="/A268977/a268977.txt">Empirical recurrence of order 54</a>
%F Empirical recurrence of order 54 (see link above)
%e Some solutions for n=2
%e ..0..0. .2..0. .0..0. .0..1. .1..0. .1..0. .0..0. .1..1. .1..0. .0..1
%e ..1..0. .1..2. .1..2. .1..0. .1..2. .0..1. .0..1. .2..2. .0..1. .0..2
%e ..1..1. .1..0. .2..2. .0..1. .1..2. .2..2. .2..2. .1..2. .0..1. .1..2
%e ..0..0. .0..0. .2..1. .2..1. .0..0. .2..1. .1..0. .1..0. .2..1. .2..2
%e ..0..1. .0..0. .2..2. .2..1. .1..2. .0..2. .1..2. .1..0. .0..0. .1..0
%e ..2..1. .0..1. .0..1. .2..2. .2..2. .1..2. .2..1. .0..1. .0..1. .0..1
%e ..2..2. .2..1. .2..2. .1..0. .2..2. .1..0. .0..1. .2..2. .0..0. .2..2
%Y Cf. A268971.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 16 2016