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Number of (n+1)X(2+1) 0..2 arrays with 2X2 subblock sum of squares lexicographically nondecreasing rowwise and nonincreasing columnwise
1

%I #4 Jan 10 2014 07:34:53

%S 432,5022,60231,533868,4740889,33788761,241566875,1459008798,

%T 8848965583,46891736689,249575149293,1188461312849,5682088960329,

%U 24740156703465,108084980986187,435986901071266,1763432694210089,6658246691642318

%N Number of (n+1)X(2+1) 0..2 arrays with 2X2 subblock sum of squares lexicographically nondecreasing rowwise and nonincreasing columnwise

%C Column 2 of A235421

%H R. H. Hardin, <a href="/A235418/b235418.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=3

%e ..2..1..1....2..0..2....1..1..0....1..0..0....1..2..0....2..0..0....1..1..0

%e ..2..2..2....0..0..0....0..1..0....2..0..0....0..1..1....1..0..2....1..0..1

%e ..2..2..1....1..2..0....2..1..2....1..2..0....2..2..1....2..0..0....2..2..0

%e ..2..2..2....2..1..1....2..0..1....0..2..2....2..1..0....1..2..1....1..1..2

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 10 2014