A128010 Numerators of rational-valued radii of circles given by 3 distinct integer points in the 4-dimensional Euclidean space.

1, 5, 3, 5, 7, 11, 2, 17, 13, 9, 7, 33, 19, 5, 13, 21, 27, 11, 14, 17, 29, 3, 37, 31, 25, 19, 13, 33, 10, 27, 17, 41, 7, 25, 18, 29, 51, 11, 37, 26, 15, 53, 19, 99, 65, 23, 27, 39, 47, 55, 91, 4, 65, 57, 49, 41, 33, 29, 25, 67, 21, 59, 17, 30, 43, 69, 13, 61, 35, 22, 53, 31, 9

Offset: 1

Author

Heinrich Ludwig, Feb 18 2007

Keywords

• frac
• nonn

Comments

A triangle in the 4-dimensional Euclidean space defines a circumcircle. There exist only certain rational-valued circumradii if the vertices of the triangle have integer coordinates. They are listed by the pair of sequences A128010/A128011 in increasing order.

Crossrefs

See A128011 for denominators. Cf. A128006, A128007, A128008, A128009.