I can be expressed as the sum of the first n cubes. What formula describes me?
Category: Math · Difficulty: hard
Hint: Think of a well-known formula that relates to triangular numbers.
Answer
((n(n + 1)) / 2)²
Explanation
The sum of the first n cubes equals the square of the nth triangular number, which is ((n(n + 1)) / 2)².
This is a hard math riddle — a tricky one that takes a little thought. The answer is ((n(n + 1)) / 2)².
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