We didn't talk about prime numbers in my class, but several of the homework problems mention them.(adsbygoogle = window.adsbygoogle || []).push({});

For instance:

Prove that if every even natural number greater than 2 is the sum of two primes, then every odd natural number greater than 5 is the sume of three primes.

Assume that n is an even natural number and n is greater than 2.

Then n=2k, where k is an integer, and 2k is greater than 2.

But how do I define a prime number in a proof?

Any hints/help would be appreciated!

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# Proofs involving prime numbers

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