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A190312 Number of scalene triangles on a (n X n)-grid (or geoboard). 1
0, 0, 40, 368, 1704, 5704, 15400, 36096, 75632, 145968, 263592, 451392, 738360, 1163552, 1774840, 2632344, 3808992, 5394752, 7493936, 10233832, 13759008, 18241312, 23877984, 30896984, 39551456, 50137240, 62983128, 78459880 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..28.

Barile, Margherita: MathWorld -- Geoboard.

Weisstein, Eric W.: MathWorld -- Scalene Triangle.

FORMULA

a(n) = A045996(n)-A186434(n).

CROSSREFS

Cf. A045996, A186434.

Sequence in context: A251431 A285919 A234913 * A229532 A252180 A008355

Adjacent sequences:  A190309 A190310 A190311 * A190313 A190314 A190315

KEYWORD

nonn

AUTHOR

Martin Renner, May 08 2011

STATUS

approved

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Last modified December 19 10:10 EST 2018. Contains 318246 sequences. (Running on oeis4.)