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A290167
Number of complete non-collateral matches with lattice points on the edges of an n X n square (symmetries and rotations excluded).
2
1, 5, 121, 9598, 1679181, 453504350, 172005077014, 86949091994273, 56483442337203525, 45847249692285567451, 45469223124152747878400, 54099446571414415140387750, 76055371931321606140937295538, 124721482827599093214246240617246
OFFSET
1,2
LINKS
EXAMPLE
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.
CROSSREFS
Cf. A139267 (number of distinct matches), A290166.
Sequence in context: A012151 A012156 A368854 * A193479 A324089 A071171
KEYWORD
nonn
AUTHOR
César Eliud Lozada, Jul 22 2017
EXTENSIONS
a(4) corrected by César Eliud Lozada, Sep 15 2017
a(5)-a(8) from Andrew Howroyd, Sep 16 2017
a(9)-a(14) from Andrew Howroyd, Sep 18 2017
STATUS
approved