HYACINTHOS 23071

Antreas Hatzipolakis

 

Let ABC be a triangle.

Denote:

Na = the NPC center of IBC

Aa Ab, Ac = the reflections of Na in AI,BI,CI

(N1) = the NPC of AaAbAc

Similary (N2), (N3).

(N1), (N2), (N3) concur (on OI line).

Point?

APH