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Prime or Composite? (2) (Posted on 2022-12-10)

Each of p and 8p² + 1 is a prime number.

Is 8p² - 1 a prime number?

If not, provide an example.
If so, prove it.

Computer program and spreadsheet aided methodologies are welcome, but an analytical solution is preferred.

*** Adapted from a problem appearing in a Russian Mathematical Olympiad.

Submitted by K Sengupta

Rating: 5.0000 (1 votes)

Solution: (Hide)

True, 8p² - 1 is a prime number.
For an explanation, refer to the analytical solution submitted by Steve Herman in this location.

Comments: ( You must be logged in to post comments.)

Subject	Author	Date
re: Concierge website services	K Sengupta	2024-03-08 11:27:48
Concierge website services	CodyDunning	2024-03-08 10:31:18
No Subject	K Sengupta	2022-12-23 18:03:27
re: No Subject	Gir Li	2022-12-23 11:14:07
No Subject	K Sengupta	2022-12-19 01:57:11
Create Logo Design for company in Dubai	jonemartin	2022-12-19 00:49:57
Analytical solution (spoiler)	Steve Herman	2022-12-10 07:39:03

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