Kobon Triangle -- from Wolfram MathWorld

Kobon Fujimura asked for the largest number N(n) of nonoverlapping triangles that can be constructed using n lines (Gardner 1983, p. 170). A Kobon triangle is therefore defined as one of the triangles constructed in such a way. The first few terms are 1, 2, 5, 7, 11, 15, 21, (OEIS A006066). It appears to be very difficult to find an analytic expression for the nth term, although Saburo Tamura has proved an upper bound on N(n) of |_n(n-2)/3_|, where |_x_| is the floor function (Eppstein).

PDF) Congruent triangles in arrangements of lines

PDF) Congruent triangles in arrangements of lines

The Kobon Triangle Problem - Futility Closet

Rahmadi tutorial wolfram alpha

Math Games: Kobon Triangles

Parallelian -- from Wolfram MathWorld

Math Games: Kobon Triangles

MEDIAN Don Steward mathematics teaching: Kobon triangles

Central Triangle -- from Wolfram MathWorld

IGS, Dynamic Geometry 1459: Two Triangles, Orthocenter, Midpoint, Perpendicular, Step-by-step Illustration, GeoGebra, iPad Apps. Typography