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%I #4 Jan 18 2017 08:43:24
%S 0,12,443,8489,105368,1113148,10598099,94350141,800540848,6552843938,
%T 52163574440,406096164959,3104415588852,23374506589595,
%U 173753114036173,1277461524990825,9303058981853048,67186844864693416,481669905249353054
%N Number of nX3 0..2 arrays with no element equal to more than one of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
%C Column 3 of A281251.
%H R. H. Hardin, <a href="/A281248/b281248.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 14*a(n-1) -37*a(n-2) -137*a(n-3) +133*a(n-4) +1003*a(n-5) +3804*a(n-6) +5187*a(n-7) -2352*a(n-8) -9604*a(n-9) -8788*a(n-10) +20660*a(n-11) +73716*a(n-12) +13836*a(n-13) -107898*a(n-14) -90512*a(n-15) +29977*a(n-16) +283636*a(n-17) +190689*a(n-18) -510519*a(n-19) -322065*a(n-20) +553505*a(n-21) +160238*a(n-22) -387019*a(n-23) +48576*a(n-24) +108354*a(n-25) -163512*a(n-26) -22652*a(n-27) +75376*a(n-28) +6952*a(n-29) +12160*a(n-30) +24352*a(n-31) +7936*a(n-32) +2432*a(n-33) +2048*a(n-34) +512*a(n-35) for n>45
%e Some solutions for n=4
%e ..0..1..2. .0..1..0. .0..1..0. .0..1..2. .0..0..1. .0..0..1. .0..1..0
%e ..0..2..1. .0..2..0. .1..0..1. .2..0..1. .1..1..2. .1..1..2. .0..0..2
%e ..1..2..2. .0..1..2. .0..1..2. .2..0..1. .2..2..0. .0..2..0. .2..1..2
%e ..2..1..0. .0..2..0. .0..2..1. .1..0..1. .1..1..0. .1..2..0. .1..0..0
%Y Cf. A281251.
%K nonn
%O 1,2
%A _R. H. Hardin_, Jan 18 2017
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