SOLUTION: I need to find a counterexample to the statement 4^n+1 is divisible by 5. Can someone please show me how to do this. Thanks

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Question 169224: I need to find a counterexample to the statement 4^n+1 is divisible by 5. Can someone please show me how to do this.
Thanks
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
I need to find a counterexample to the statement 4%5En%2B1
is divisible by 5. Can someone please show me how to do this.

Start with n=1.

4%5E1%2B1+=+4%2B1+=+5

No. that's not it, because 5 is divisible by 5.

So try n=2

4%5E2%2B1=16%2B1=17

There your counterexample. 17 is not divisible by 5.

Edwin