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%I #4 Mar 09 2017 18:24:44
%S 0,1,20,270,2763,26662,241796,2115564,18020972,150431216,1235860816,
%T 10022560088,80412418752,639331124272,5043680344120,39521427506168,
%U 307850445104320,2385411084242780,18397022091700304,141285768645661084
%N Number of nX3 0..1 arrays with no 1 equal to more than three of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements.
%C Column 3 of A283522.
%H R. H. Hardin, <a href="/A283517/b283517.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 15*a(n-1) -36*a(n-2) -235*a(n-3) +171*a(n-4) +2481*a(n-5) +5734*a(n-6) +6894*a(n-7) +5364*a(n-8) +3397*a(n-9) +1947*a(n-10) +846*a(n-11) +277*a(n-12) +126*a(n-13) +12*a(n-14) +8*a(n-15) for n>19
%e Some solutions for n=4
%e ..1..1..1. .1..0..0. .1..0..1. .1..0..0. .0..1..1. .0..0..0. .1..0..1
%e ..1..1..0. .1..1..1. .1..1..1. .0..1..1. .1..1..1. .0..1..0. .1..1..0
%e ..0..1..1. .1..1..1. .0..1..0. .1..1..1. .0..1..1. .1..1..1. .1..1..0
%e ..0..0..1. .0..0..1. .1..1..1. .0..1..1. .0..0..1. .1..1..1. .1..0..1
%Y Cf. A283522.
%K nonn
%O 1,3
%A _R. H. Hardin_, Mar 09 2017
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