%I #10 Nov 16 2016 15:51:45
%S 1,142,4699,77970,672506,4338248,21167201,85351595,294664274,
%T 911848844,2528561187,6501165477
%N Number of nonequivalent (mod D_4) ways to arrange 6 points on an n X n square grid so that no three points are collinear.
%C Column 6 of A235453.
%C Without the restriction "nonequivalent (mod D_4)" the numbers are given by A194191, n >= 3.
%e There is a(3) = 1 way to place 6 points (X) on a 3 X 3 grid (without rotations and reflections):
%e . X X
%e X . X
%e X X .
%Y Cf. A235453, A194191, A235454 (3 points), A235455 (4 points), A235456 (5 points), A235458 (7 points).
%K nonn,more
%O 3,2
%A _Heinrich Ludwig_, Jan 12 2014
%E a(13), a(14) from _Heinrich Ludwig_, Nov 16 2016
