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%I #4 Jun 18 2012 07:07:44
%S 529,750261,109820000,4286833981,83545858925,976919547736,
%T 8159542628448,51964311225934,271341777491743,1197645088919101,
%U 4637119560078960,16013821321719463,50395763900241707,145985579644461562
%N Half the number of 5X5 0..n symmetric arrays with no 2X2 subblock summing to 2n
%C Row 4 of A213697
%H R. H. Hardin, <a href="/A213700/b213700.txt">Table of n, a(n) for n = 1..33</a>
%e Some solutions for n=4
%e ..0..3..2..3..4....3..0..0..1..4....0..4..0..2..3....0..1..2..2..4
%e ..3..4..3..1..3....0..2..3..1..1....4..2..0..3..3....1..2..4..1..0
%e ..2..3..4..2..4....0..3..2..4..3....0..0..4..3..1....2..4..2..3..1
%e ..3..1..2..4..1....1..1..4..1..4....2..3..3..2..0....2..1..3..1..4
%e ..4..3..4..1..1....4..1..3..4..3....3..3..1..0..4....4..0..1..4..4
%K nonn
%O 1,1
%A _R. H. Hardin_ Jun 18 2012