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A192493 Numerators of squared radii of circumcircles of non-degenerate triangles with integer vertex coordinates. 7
1, 1, 5, 25, 25, 2, 5, 25, 25, 13, 325, 169, 65, 4, 65, 17, 425, 221, 9, 289, 1105, 169, 85, 5, 325, 85, 50, 1105, 289, 25, 2125, 625, 13, 325, 425, 1625, 169, 1105, 125, 65, 29, 2465, 4225, 1885, 725, 377, 2465, 5525, 1885, 125, 8, 145, 65, 841, 17, 841, 845, 425, 2125, 221, 6409, 9425, 9, 325, 289, 145, 1105, 37, 5365, 3145, 169, 2405, 925, 85, 1369, 4625, 481, 625, 493, 2405, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Hugo Pfoertner, Table of n, a(n) for n = 1..9089, covering range R^2 <= 100.

Hugo Pfoertner, Circles Passing through 3 Points of the Square Lattice, illustrations up to R^2=10.

EXAMPLE

The smallest triangle of lattice points {(0,0),(1,0),(0,1)} has circumradius R=sqrt(2)/2, i.e., R^2=1/2. Therefore a(1)=1, A192494(1)=2.

CROSSREFS

Cf. A192494 (corresponding denominators), A128006, A128007.

Sequence in context: A036139 A070382 A271379 * A265973 A265928 A039936

Adjacent sequences:  A192490 A192491 A192492 * A192494 A192495 A192496

KEYWORD

nonn,frac

AUTHOR

Hugo Pfoertner, Jul 10 2011

STATUS

approved

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Last modified June 3 05:29 EDT 2020. Contains 334798 sequences. (Running on oeis4.)