2015 AMC 12B Problems/Problem 20
Problem
For every positive integer , let
be the remainder obtained when
is divided by 5. Define a function
recursively as follows:
What is ?
Solution
Simply draw a table of values of for the first few values of
:
It is now clear that for ,
for all values
.
Thus, .
See Also
2015 AMC 12B (Problems • Answer Key • Resources) | |
Preceded by Problem 19 |
Followed by Problem 21 |
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