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%I #8 Apr 14 2015 08:32:52
%S 256,1868,1868,14096,37652,14096,111900,762508,762508,111900,912848,
%T 16547988,39065788,16547988,912848,7609244,367558796,2178706440,
%U 2178706440,367558796,7609244,64386416,8327731884,122764464080
%N T(n,k) = Number of (n+1) X (k+1) 0..3 arrays with the maximum plus the minimum of every 2 X 2 subblock equal.
%C Table starts:
%C .....256.......1868.........14096...........111900..............912848
%C ....1868......37652........762508.........16547988...........367558796
%C ...14096.....762508......39065788.......2178706440........122764464080
%C ..111900...16547988....2178706440.....317411030268......46125739204336
%C ..912848..367558796..122764464080...46125739204336...17061532793217332
%C .7609244.8327731884.7033328776428.6800622630757224.6399495495536326520
%H R. H. Hardin, <a href="/A237158/b237158.txt">Table of n, a(n) for n = 1..112</a>
%F Empirical for column k:
%F k=1: [linear recurrence of order 10]
%F k=2: [order 16]
%F k=3: [order 38]
%F k=4: [order 84]
%e Some solutions for n=2, k=4:
%e ..0..0..0..3..1....0..0..0..0..2....0..0..0..3..1....0..0..0..0..1
%e ..0..3..0..0..2....0..3..1..3..3....0..3..0..3..0....0..3..3..1..3
%e ..2..0..2..3..1....2..2..0..1..0....1..2..0..0..3....0..3..0..0..3
%K nonn,tabl
%O 1,1
%A _R. H. Hardin_, Feb 04 2014