perplexus.info :: Just Math : Choose To Prime Poser

Choose To Prime Poser (Posted on 2010-04-18)

Determine all possible values of a positive integer N ≥ 3, such that ^NC₂ – 1 is a prime power.

Note: ^NC₂ represents N choose 2.

Submitted by K Sengupta

Rating: 5.0000 (1 votes)

Solution: (Hide)

N = 3,4,5,8 are the only values that satisfy the given conditions.

For an explanation, refer to the solution submitted by Jer in this location.

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

Subject	Author	Date
re(2): No Subject. No real hole in my proof.	Jer	2010-04-26 15:42:02
re: No Subject	farcear	2010-04-24 22:10:51
No Subject	Jer	2010-04-23 16:28:43
computer exploration (spoilers) possible solution	Charlie	2010-04-18 13:45:26

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