Let H=X(4)-Orthocenter of ABC. A1B1C1 cevian triangle of H. B1A, C1A are reflections of B1, C1 on A.
LA, line through B1A, C1A. define LB, LC cyclically.
A2B2C2 triangle bounded by lines LA, LB, LC.
* Circumcenter of A2B2C2 lies on Euler line of ABC.
