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%I #4 Jan 10 2017 10:26:34
%S 0,1,10,213,2292,21762,184076,1457827,11000888,80107879,567420546,
%T 3931417538,26752272278,179329108005,1186930999936,7770945222145,
%U 50399529101088,324186782002754,2070149445768880,13133990417566391
%N Number of 2Xn 0..2 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
%C Row 2 of A280902.
%H R. H. Hardin, <a href="/A280903/b280903.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 15*a(n-1) -57*a(n-2) -88*a(n-3) +651*a(n-4) +333*a(n-5) -2520*a(n-6) -939*a(n-7) +4569*a(n-8) +1456*a(n-9) -4131*a(n-10) -933*a(n-11) +1793*a(n-12) +60*a(n-13) -336*a(n-14) +64*a(n-15) for n>17
%e Some solutions for n=4
%e ..0..1..2..1. .0..1..2..0. .0..1..2..2. .0..1..1..2. .0..1..2..0
%e ..0..2..2..2. .2..2..0..0. .2..2..0..2. .1..2..2..2. .1..1..1..0
%Y Cf. A280902.
%K nonn
%O 1,3
%A _R. H. Hardin_, Jan 10 2017
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