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%I #14 May 25 2019 01:40:42
%S 0,1,6,20,55,119,229,402,667,1019,1536,2216,3049,4168,5546,7203,9278,
%T 11755,14597,18054,22138,26625,31958,38120,44821,52764,61663,71204,
%U 82250,94479,107680,122740,139224,156699,176450,198176,220883
%N Similarity classes of triangles which can be drawn using the lattice points in an n X n grid for vertices.
%H Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a028/A028492.java">Java program</a> (github)
%H D. Rusin, <a href="http://www.math.niu.edu/~rusin/known-math/97/triangles.grid">Lattice Problem (Triangles)</a> [Broken link]
%H D. Rusin, <a href="/A028419/a028419.grid.txt">Lattice Problem (Triangles)</a> [Cached copy]
%Y Cf. A028419.
%K nonn
%O 0,3
%A _David J. Rusin_
%E Extended by _Ray Chandler_, May 03 2011