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A229376 Number of nX4 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 diagonally or antidiagonally.

%I A229376 #6 Jul 23 2025 05:41:43
%S A229376 60,518,6730,78690,956866,11441370,138118032,1657198220,19969628086,
%T A229376 239888727922,2888372417962,34717775838484,417835837510270,
%U A229376 5023955278338394,60449751205860716,726964181424486002
%N A229376 Number of nX4 0..2 arrays avoiding 11 horizontally, 22 vertically and 00 diagonally or antidiagonally.
%C A229376 Column 4 of A229380
%H A229376 R. H. Hardin, <a href="/A229376/b229376.txt">Table of n, a(n) for n = 1..210</a>
%F A229376 Empirical: a(n) = 6*a(n-1) +150*a(n-2) -614*a(n-3) -6021*a(n-4) +20473*a(n-5) +101559*a(n-6) -313078*a(n-7) -812145*a(n-8) +2419449*a(n-9) +3153273*a(n-10) -9572428*a(n-11) -6094709*a(n-12) +19880682*a(n-13) +5584682*a(n-14) -21686564*a(n-15) -1854284*a(n-16) +12002158*a(n-17) -190196*a(n-18) -3154524*a(n-19) +224356*a(n-20) +344336*a(n-21) -35568*a(n-22) -12480*a(n-23) +1536*a(n-24) for n>25
%e A229376 Some solutions for n=4
%e A229376 ..1..0..0..1....1..2..2..1....2..2..2..1....2..0..1..2....0..0..1..2
%e A229376 ..2..1..2..2....0..0..1..0....1..0..0..1....1..2..1..0....2..2..2..0
%e A229376 ..0..1..0..1....1..2..1..0....2..2..2..1....1..0..1..0....1..0..1..0
%e A229376 ..2..1..2..2....0..0..2..0....0..0..1..2....1..0..2..1....1..0..2..2
%K A229376 nonn
%O A229376 1,1
%A A229376 _R. H. Hardin_ Sep 21 2013