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.

See The Solution Submitted by K Sengupta

Rating: 5.0000 (1 votes)

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re: No Subject

| Comment 3 of 4 |

(In reply to No Subject by Jer)

"(B) Both factors are powers of 3."

Why must that be true?

Posted by farcear on 2010-04-24 22:10:51

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