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%I #22 Jan 17 2023 04:35:36
%S 0,0,8,54,228,708,1980,4890,11528,26004,57384,123786,265596,563664,
%T 1192220,2511474,5279208,11064216,23156448,48361110,100859180,
%U 209996772,436635396,906562842,1879950384,3893566872,8054935784,16645591974,34363631412,70872295524,146036933100
%N Number of ways to select 3 or more collinear points from an n X n grid.
%H Lucas A. Brown, <a href="/A355553/b355553.txt">Table of n, a(n) for n = 1..71</a>
%H Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/A355553.py">A355553.py</a>.
%e a(4)=54: There are 4 horizontal lines of length 4 and within a line of 4 dots are 5 ways to select a line 3 or longer. There are 2 diagonal lines of length 4 and 4 vertical lines of length 4. Finally there are 4 diagonals of length 3 these are: ((1,2),(2,3),(3,4)),((2,1),(3,2),(4,3)),((1,3),(2,2),(3,1)),((2,4),(3,3),(4,2). In total we have 5*10+4=54.
%e 4 . . . .
%e 3 . . . .
%e 2 . . . .
%e 1 . . . .
%e 1 2 3 4
%Y Cf. A000982 (1 X n), 2*A000982 (2 X n), A355551 (3 X n), A355552 (4 X n).
%K nonn
%O 1,3
%A _Thomas Garrison_, Jul 14 2022
%E Corrected and extended by _Lucas A. Brown_, Nov 06 2022
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