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%I #8 Dec 09 2017 03:57:21
%S 0,0,0,204,26700,1073076,15657764,159413700,1108580092,6030207624,
%T 26852315940,104865006648,354993232192,1098793355508,3109294280324
%N Number of ways to arrange 7 indistinguishable points on an n X n square grid so that no three points are collinear at any angle.
%C Column 7 of A194193.
%e Some solutions for 4 X 4:
%e ..0..0..1..1....1..0..1..0....0..0..1..0....0..0..0..1....1..0..1..0
%e ..0..0..0..1....0..0..0..1....0..0..1..1....1..0..1..0....0..1..0..0
%e ..1..1..0..0....0..1..0..1....1..1..0..0....1..0..1..0....0..1..0..1
%e ..0..1..1..0....0..1..1..0....0..1..0..1....0..1..0..1....1..0..1..0
%K nonn
%O 1,4
%A _R. H. Hardin_, Aug 18 2011