2009 UNCO Math Contest II Problems/Problem 2

Revision as of 09:45, 26 November 2016 by Mathisfun04 (talk | contribs) (Solution)

Problem

(a) Let $Q_n=1^n+2^n$. For how many $n$ between $1$ and $100$ inclusive is $Q_n$ a multiple of $5$?

(b) For how many $n$ between $1$ and $100$ inclusive is $R_n=1^n+2^n+3^n+4^n$ a multiple of 5?


Solution

This problem needs a solution. If you have a solution for it, please help us out by adding it.

See also

2009 UNCO Math Contest II (ProblemsAnswer KeyResources)
Preceded by
Problem 1
Followed by
Problem 3
1 2 3 4 5 6 7 8 9 10
All UNCO Math Contest Problems and Solutions
Invalid username
Login to AoPS