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A240279 Number of nX2 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4.

%I A240279 #7 Jun 02 2025 09:46:10
%S A240279 2,8,19,38,114,251,612,1656,3758,9630,24258,57548,146898,360946,
%T A240279 880960,2217967,5429271,13419200,33424298,82079277,203571196,
%U A240279 504206276,1242741927,3081338174,7616293969,18815746878,46600839533,115150972966
%N A240279 Number of nX2 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4.
%C A240279 Column 2 of A240284
%H A240279 R. H. Hardin, <a href="/A240279/b240279.txt">Table of n, a(n) for n = 1..210</a>
%F A240279 Empirical: a(n) = 3*a(n-2) +10*a(n-3) -3*a(n-4) -6*a(n-5) -3*a(n-6) +8*a(n-7) -7*a(n-8) -9*a(n-9) -4*a(n-10) +13*a(n-11) -14*a(n-12) +17*a(n-13) -a(n-15)
%e A240279 Some solutions for n=4
%e A240279 ..3..1....3..1....3..3....3..3....3..1....3..3....3..1....3..1....3..1....3..1
%e A240279 ..2..0....3..1....2..2....3..2....3..1....3..2....2..2....2..0....3..1....2..0
%e A240279 ..2..0....2..1....2..1....2..1....3..2....3..1....2..0....2..1....3..1....2..0
%e A240279 ..2..1....3..3....2..1....3..1....2..1....2..1....3..3....3..3....2..2....3..1
%K A240279 nonn
%O A240279 1,1
%A A240279 _R. H. Hardin_, Apr 03 2014