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%I #4 Feb 01 2014 07:56:34
%S 339,3205,30644,337861,3782769,43538228,504121651,5869125835,
%T 68447883704,799193185177,9335513529061,109078340464240,
%U 1274639900671115,14895774356170087,174080704237509648,2034438282599485301
%N Number of (n+1)X(2+1) 0..2 arrays with the maximum plus the upper median of every 2X2 subblock equal
%C Column 2 of A236902
%H R. H. Hardin, <a href="/A236896/b236896.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 20*a(n-1) -50*a(n-2) -1079*a(n-3) +5929*a(n-4) +13546*a(n-5) -136152*a(n-6) +32559*a(n-7) +1230196*a(n-8) -1321510*a(n-9) -5558982*a(n-10) +8606104*a(n-11) +13433556*a(n-12) -26908536*a(n-13) -16223728*a(n-14) +45800336*a(n-15) +5469360*a(n-16) -41824640*a(n-17) +6747552*a(n-18) +17907200*a(n-19) -5889280*a(n-20) -2304000*a(n-21) +921600*a(n-22)
%e Some solutions for n=3
%e ..0..2..2....1..2..2....0..2..2....0..2..0....1..2..0....0..2..1....1..2..1
%e ..0..2..1....0..2..1....2..2..0....1..2..1....1..2..2....0..1..0....2..1..2
%e ..0..2..2....1..2..2....2..2..0....1..2..0....2..1..2....1..2..1....2..2..1
%e ..2..2..1....0..2..0....2..1..2....1..2..1....0..2..1....1..1..1....2..2..1
%K nonn
%O 1,1
%A _R. H. Hardin_, Feb 01 2014