Difference between revisions of "2018 UNCO Math Contest II Problems/Problem 11"

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

Revision as of 00:32, 14 January 2019

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 (ProblemsAnswer KeyResources)
Preceded by
Problem 10
Followed by
Last Question
1 2 3 4 5 6 7 8 9 10
All UNCO Math Contest Problems and Solutions

[[Category:]]