Learn Tetrahedral Number | Triangular pyramidal number

 What do you mean by Tetrahedral Number?

Tetrahedral Numbers Definition

A tetrahedral number is known as triangular pyramidal number.

A Tetrahedron is a figurate number that represents a pyramid with a triangular base and three sides.

The nth tetrahedral number is the sum of the first n triangular numbers.

First 10 Tetrahedral Numbers

1, 4, 10, 20, 35, 56, 84, 120, 165, 220

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