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%I #4 Jun 30 2012 11:54:30
%S 172,1003,2546,8168,14030,28328,40370,64679,102377,151301,191708,
%T 290679,356931,445149,569583,787170,917169,1190970,1375176,1744554,
%U 2061684,2413461,2647641,3323763,3962721,4502277,5124586,6087406,6704266,7973326
%N Number of 3X3 0..n matrices whose square is also a 0..n matrix
%C Row 3 of A213990
%H R. H. Hardin, <a href="/A213992/b213992.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=3
%e ..0..0..2....1..2..1....0..3..0....0..2..1....0..1..3....1..1..0....0..1..0
%e ..0..1..1....0..0..0....0..1..1....0..0..0....0..0..1....0..0..3....0..1..0
%e ..0..1..1....1..0..0....0..2..0....0..0..1....0..0..0....0..0..0....0..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Jun 30 2012