दोनों विकर्णों द्वारा विभाजित एक साधारण वर्ग में कितने त्रिभुज होते हैं?

How many triangles are there in a standard 4-level triangular grid (like a Tetractys or standard triangle counting puzzle with 4 base segments)?

A standard triangular grid diagram contains a set of intersecting lines forming smaller geometric units. If a grid is composed of a main triangle divided into 3 layers with minor vertical subdivisions yielding a total count, what is the exact number of triangles present in a standard 4-tier benchmark triangular puzzle containing 19 unique triangles?