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%I #7 Jan 20 2024 16:19:27
%S 81,426,2269,12004,63945,339684,1806104,9590924,50981860,270885808,
%T 1439698020,7649649584,40652677572,216021080080,1147974683632,
%U 6100208729024,32416974402064,172262578560928,915411064116880
%N Number of (n+1) X (1+1) 0..2 arrays colored with the maximum plus the lower median minus the minimum of every 2 X 2 subblock.
%C Column 1 of A236610.
%H R. H. Hardin, <a href="/A236604/b236604.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 28*a(n-3) +336*a(n-4) +744*a(n-5) +3360*a(n-6) +6176*a(n-7) +8308*a(n-8) +14576*a(n-9) -20528*a(n-10) -34304*a(n-11) -86784*a(n-12) -144128*a(n-13) +1536*a(n-14) +8192*a(n-15) +147456*a(n-16) +229376*a(n-17).
%e Some solutions for n=5
%e ..0..1....2..0....1..1....0..1....1..1....2..1....1..2....2..1....0..1....2..1
%e ..2..1....1..0....0..1....0..2....1..1....0..1....1..0....1..0....0..0....0..2
%e ..1..2....1..0....1..0....2..2....2..1....2..0....1..0....1..0....0..0....2..0
%e ..0..2....2..0....1..1....2..2....0..1....2..1....1..1....2..0....1..1....1..2
%e ..0..1....2..2....0..0....1..2....1..0....0..0....1..1....2..2....1..2....2..1
%e ..2..2....1..0....0..0....2..1....2..2....1..1....0..1....2..2....2..0....0..1
%Y Cf. A236610.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 29 2014