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%I #20 Jun 15 2020 21:39:18
%S 0,0,0,10,64,234,660,1524,3156,5928,10428,17154,27340,41506,61176,
%T 87756,123216,168420,227208,300054,391920,504886,642604,806424,
%U 1006404,1242024,1519980,1845150,2226804,2663574,3175048,3754936,4420440,5175840,6030840
%N Number of ways to choose four collinear points from an n X n grid.
%H Tomas Rokicki and Tom Duff, <a href="/A178256/b178256.txt">Table of n, a(n) for n = 1..1000</a> (First 48 terms from R. H. Hardin.)
%e a(1) = a(2) = a(3) = 0 since there are no collinear point quadruples
%e a(4) = 4 rows + 4 columns + 2 diagonals = 10
%e a(5) = binomial(5,4)*(5 rows + 5 columns + 2 diagonals) + 4 secondary diagonals = 64
%e a(6) = binomial(6,4)*(6 rows + 6 columns + 2 diagonals) + binomial(5,4)*(4 secondary diagonals) + 4 third diagonals = 234
%Y Cf. A000938, A157882.
%Y This is the main diagonal of A334708.
%K nonn
%O 1,4
%A _R. H. Hardin_, suggested by R. J. Mathar in the Sequence Fans Mailing List, May 24 2010
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