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2018 UNCO Math Contest II Problems/Problem 11

Revision as of 00:32, 14 January 2019 by Timneh (talk | contribs) (→‎Problem)

Problem

(a) Find an integer $n > 1$ for which $1 + 2 + \ldots + n^2$ is a perfect square. (b) Show that there are infinitely many integers $n > 1$ that have the property that $1 + 2 + \ldots + n^2$ is a perfect square, and determine at least three more examples of such $n$. Hint: There is one approach that uses the result of a previous problem on this contest.

Solution

See also

2018 UNCO Math Contest II (Problems • Answer Key • Resources)
Preceded by
Problem 10 		Followed by
Last Question
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All UNCO Math Contest Problems and Solutions

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