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%I #9 Feb 09 2019 08:49:19
%S 0,4,47,395,3453,30475,268257,2360984,20781746,182923358,1610107387,
%T 14172312272,124745996060,1098025707095,9664923050975,85071539806558,
%U 748807501780793,6591072360831728,58015223889383283,510655325670196475
%N Number of n X 2 0..3 arrays with every element plus 1 mod 4 equal to some element at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) (1,-1) or (1,0), with upper left element zero.
%H R. H. Hardin, <a href="/A278267/b278267.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 10*a(n-1) - 14*a(n-2) + 37*a(n-3) - 65*a(n-4) + 70*a(n-5) - 76*a(n-6) + 74*a(n-7) - 32*a(n-8).
%F Empirical g.f.: x^2*(4 + 7*x - 19*x^2 + 13*x^3 - 4*x^4 + 9*x^5 - 8*x^6) / (1 - 10*x + 14*x^2 - 37*x^3 + 65*x^4 - 70*x^5 + 76*x^6 - 74*x^7 + 32*x^8). - _Colin Barker_, Feb 09 2019
%e Some solutions for n=4:
%e ..0..2. .0..3. .0..2. .0..3. .0..1. .0..2. .0..2. .0..3. .0..0. .0..3
%e ..1..3. .1..2. .1..3. .1..2. .0..2. .1..3. .1..3. .1..2. .1..3. .1..2
%e ..3..0. .3..0. .0..2. .0..2. .3..2. .2..3. .2..2. .1..3. .2..1. .1..1
%e ..2..2. .2..1. .3..3. .3..3. .1..1. .0..1. .0..1. .0..2. .0..3. .0..3
%Y Column 2 of A278272.
%K nonn
%O 1,2
%A _R. H. Hardin_, Nov 16 2016
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