%I
%S 1,13,70,290,867,2266,5068,10475,19764,35406,59817,97375,152154
%N Number of nonequivalent (mod D_4) ways to arrange 3 points on an n X n square grid so that they are not collinear.
%C Column 3 of A235453.
%C Also number of nonequivalent triangles in an n X n grid.
%C Without the restriction "nonequivalent (mod D_4)" the numbers are given by A045996, n >= 2.
%e There are a(3) = 13 nonequivalent ways to place 3 points on a 3 X 3 grid:
%e . . . . . . X . . . X . . . . . X . . X .
%e X . . X . . . . . . . . . X . X . X X X .
%e X X . X . X X . X X . X X . X . . . . . .
%e 
%e . . . . . . . . . . X . . X . . . X
%e X . X . X X X X . . . X X . . X . .
%e X . . X . . X . . X . . X . . X . .
%Y Cf. A235453, A045996, A235455 (4 points), A235456 (5 points), A235457 (6 points), A235458 (7 points).
%K nonn,more
%O 2,2
%A _Heinrich Ludwig_, Jan 12 2014
%E a(13), a(14) from _Heinrich Ludwig_, Nov 16 2016
