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%I #28 Sep 18 2017 15:57:32
%S 1,5,121,9598,1679181,453504350,172005077014,86949091994273,
%T 56483442337203525,45847249692285567451,45469223124152747878400,
%U 54099446571414415140387750,76055371931321606140937295538,124721482827599093214246240617246
%N Number of complete non-collateral matches with lattice points on the edges of an n X n square (symmetries and rotations excluded).
%H César Eliud Lozada, <a href="/A290167/a290167_1.pdf">Complete matches</a>
%H Andrew Howroyd, <a href="/A290167/a290167.txt">PARI script and formula</a>
%e Points on the sides of a 2 X 2 square can be matched in 13 different ways, if matching two points on the same side is not allowed. Only 5 of these are not symmetries or reflections of the others, so a(2) = 5.
%Y Cf. A139267 (number of distinct matches), A290166.
%K nonn
%O 1,2
%A _César Eliud Lozada_, Jul 22 2017
%E a(4) corrected by _César Eliud Lozada_, Sep 15 2017
%E a(5)-a(8) from _Andrew Howroyd_, Sep 16 2017
%E a(9)-a(14) from _Andrew Howroyd_, Sep 18 2017