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A362014
Number of distinct lines passing through exactly two points in a triangular grid of side n.
0
0, 0, 3, 6, 18, 39, 81, 141, 237, 369, 561, 801, 1119, 1521, 2043, 2667, 3429, 4329, 5415, 6675, 8163, 9879, 11877, 14127, 16695, 19593, 22881, 26523, 30591, 35085, 40089, 45591, 51681, 58359, 65715, 73701, 82389, 91791, 102015, 113007, 124875
OFFSET
0,3
FORMULA
a(n) = A244504(n) - A234248(n). - Andrew Howroyd, Apr 03 2023
CROSSREFS
Cf. A234248, A244504 (lines which contain 2 or more points), A050534 (total number of pairs of points). Both are upper bounds.
Sequence in context: A026532 A160505 A081150 * A216813 A356766 A181037
KEYWORD
nonn
AUTHOR
Caleb Stanford, Apr 03 2023
STATUS
approved