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%I #8 Jan 20 2019 08:39:30
%S 216,9612,400428,15289548,555862380,19558138380,672230393004,
%T 22702294138188,756261535626732,24917784636315276,813662963240248620,
%U 26370904678702613964,849277413026034547308,27202597468298860880652
%N Number of n X 4 0..3 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling three no more than once.
%H R. H. Hardin, <a href="/A269197/b269197.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 62*a(n-1) - 1031*a(n-2) + 2180*a(n-3) - 1535*a(n-4) + 350*a(n-5) - 25*a(n-6) for n>7.
%F Empirical g.f.: 12*x*(18 - 315*x + 2265*x^2 - 8158*x^3 + 10756*x^4 - 4951*x^5 + 897*x^6) / ((1 - x)^2*(1 - 30*x + 5*x^2)^2). - _Colin Barker_, Jan 20 2019
%e Some solutions for n=2:
%e ..1..0..0..1. .1..3..1..2. .3..1..0..1. .0..2..2..2. .1..0..1..3
%e ..0..1..1..3. .2..3..2..3. .0..1..3..2. .3..2..3..0. .1..1..1..0
%Y Column 4 of A269201.
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 20 2016
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