A334712 - cp's OEIS frontend

A334712 Number of ways to select four points from an n X n grid so that three of them form a triangle of nonzero area and the extra point is strictly inside the triangle.

%I A334712 #27 Jun 23 2020 14:29:49
%S A334712 0,0,8,240,2100,11604,45184,145648,399656,976552,2172328,4500816,
%T A334712 8736172,16135996,28493760,48400296,79500936,126909720,197253768,
%U A334712 299683032,445664700,650291092,932742112,1317391344,1833532544,2518622024,3417812896,4585946096,6088659404,8006284316,10430982968,13476148160
%N A334712 Number of ways to select four points from an n X n grid so that three of them form a triangle of nonzero area and the extra point is strictly inside the triangle.
%C A334712 Computed by _Tom Duff_, Jun 15 2020 - Jun 22 2020
%H A334712 Tom Duff, <a href="/A334712/b334712.txt">Table of n, a(n) for n = 1..192</a>
%H A334712 Tom Duff, <a href="/A334708/a334708_3.txt">Data for tables A334708, A334709, A334710, A334711 for grids of size up to 192 X 192</a>
%Y A334712 The main diagonal of A334709.
%K A334712 nonn
%O A334712 1,3
%A A334712 _N. J. A. Sloane_, Jun 15 2020

cp's OEIS Frontend

A334712 Number of ways to select four points from an n X n grid so that three of them form a triangle of nonzero area and the extra point is strictly inside the triangle.