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A240401 Number of nX2 0..3 arrays with no element equal to one plus the sum of elements to its left or three plus the sum of elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4.

%I A240401 #7 Jun 02 2025 09:54:39
%S A240401 2,5,14,24,77,182,397,1164,2626,6439,17045,39465,100175,251538,602316,
%T A240401 1525842,3756635,9193532,23052218,56571408,139814332,347712483,
%U A240401 855278021,2119654735,5248572774,12946151193,32079791328,79306295913,195965663917
%N A240401 Number of nX2 0..3 arrays with no element equal to one plus the sum of elements to its left or three plus the sum of elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4.
%C A240401 Column 2 of A240406
%H A240401 R. H. Hardin, <a href="/A240401/b240401.txt">Table of n, a(n) for n = 1..210</a>
%F A240401 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 A240401 Some solutions for n=4
%e A240401 ..2..1....2..2....2..2....2..1....2..1....2..1....2..2....2..1....2..1....2..2
%e A240401 ..3..3....2..0....2..0....2..1....3..3....2..1....3..3....3..3....3..3....3..3
%e A240401 ..3..2....2..0....2..0....2..0....2..0....2..0....3..2....3..2....2..1....3..1
%e A240401 ..2..2....2..0....3..3....2..0....3..1....3..3....2..1....2..0....3..1....2..0
%K A240401 nonn
%O A240401 1,1
%A A240401 _R. H. Hardin_, Apr 04 2014