What is the smallest square triangular number whose triangular side is the square of a composite number?
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- Square numbers are those which can be arranged into a square as below, i.e., 1, 4, 9, 16, 25, etc.
- Triangular numbers are those which can be arranged into a triangle as below, e.g., 1, 3, 6, 10, 15, 21, etc.
A square triangular number is a number which is both square and triangular. A composite number is one which can be factorized (in other words, a non-prime number greater than 1). |