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A241284 Number of 2Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.

%I A241284 #6 Jun 02 2025 10:03:47
%S A241284 4,3,5,13,17,35,90,141,288,670,1101,2265,4995,8474,17477,37329,64894,
%T A241284 133967,279966,496683,1023868,2105032,3799717,7810452,15858460,
%U A241284 29052053,59504463,119660776,221989407,452920894,904106577,1695187559,3445124586
%N A241284 Number of 2Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.
%C A241284 Row 2 of A241283
%H A241284 R. H. Hardin, <a href="/A241284/b241284.txt">Table of n, a(n) for n = 1..210</a>
%F A241284 Empirical: a(n) = a(n-1) +a(n-2) +7*a(n-3) -8*a(n-4) -7*a(n-5) +9*a(n-7) +10*a(n-8) -24*a(n-9) +5*a(n-10) +29*a(n-11) -18*a(n-12) -10*a(n-13) -10*a(n-14) +16*a(n-15) +12*a(n-16) -12*a(n-17) for n>18
%e A241284 Some solutions for n=4
%e A241284 ..3..3..2..3....3..2..3..2....3..3..2..3....3..3..2..3....3..3..2..2
%e A241284 ..2..1..1..0....2..1..1..3....2..1..3..0....2..2..3..2....2..1..1..0
%K A241284 nonn
%O A241284 1,1
%A A241284 _R. H. Hardin_, Apr 18 2014