- Any of the series of numbers (1, 3, 6, 10, 15, etc.) obtained by continued summation of the natural numbers 1, 2, 3, 4, 5, etc..More example sentences
- This triangle has an elementary use in probability and combinatorics, and both the series of triangular numbers and the Fibonacci series can be derived from it.
- The triangular numbers and the Fibonacci numbers can be found in Pascal's triangle.
- Pythagoras studied properties of numbers which would be familiar to mathematicians today, such as even and odd numbers, triangular numbers, perfect numbers etc.
More definitions of triangular numberDefinition of triangular number in:
- The British & World English dictionary