Problem 810

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Caesum
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Joined: Sat Jul 29, 2023 2:19 pm

Problem 810

Post by Caesum »

Problem 810 (View Problem)
Xor primes are listed as 2,3,7...
But since 7 = 5 xor 2, why is 7 an Xor prime? Are we just to consider if it is an xor of lower xor-primes?
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RobertStanforth
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Re: Problem 810

Post by RobertStanforth »

Caesum wrote: Sat Jul 29, 2023 2:21 pm Problem 810 (View Problem)
Xor primes are listed as 2,3,7...
But since 7 = 5 xor 2, why is 7 an Xor prime? Are we just to consider if it is an xor of lower xor-primes?
Note that $\oplus$ (XOR) and $\otimes$ (Xor product) are distinct operators.
$7 = 5 \oplus 2$, but a Xor prime is a positive integer that cannot be decomposed non-trivially via $\otimes$.
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