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%I #9 Nov 30 2018 10:04:57
%S 186,2270,27844,341718,4194002,51474508,631765770,7753896830,
%T 95166467620,1168013551254,14335465950002,175944520325356,
%U 2159432720260170,26503523182815518,325287625083982468,3992376345699782742
%N Number of (n+1) X (1+1) 0..3 arrays with every 2 X 2 subblock summing to 4 5 6 7 or 8.
%H R. H. Hardin, <a href="/A251492/b251492.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 13*a(n-1) - 5*a(n-2) - 52*a(n-3) + 48*a(n-4).
%F Empirical g.f.: 2*x*(93 - 74*x - 368*x^2 + 384*x^3) / (1 - 13*x + 5*x^2 + 52*x^3 - 48*x^4). - _Colin Barker_, Nov 29 2018
%e Some solutions for n=3:
%e ..0..2....3..0....0..3....2..1....2..1....0..1....0..2....0..0....2..1....0..2
%e ..3..2....0..1....1..2....3..0....1..3....3..1....2..2....3..3....0..3....2..2
%e ..0..3....2..1....1..2....2..0....0..1....3..0....0..2....2..0....1..1....0..3
%e ..0..1....1..1....3..1....2..3....1..3....0..2....0..2....0..3....1..2....0..2
%Y Column 1 of A251499.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 03 2014
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