Problem 981. Find nearest prime number less than input number

Created by Reza Ahmadzadeh

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Last Solution submitted on May 27, 2023

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@bmtran (Bryant Tran) on 10 Oct 2012

1 isn't a prime number

Disha on 31 Jul 2013

agree @bmtran...

Grzegorz Knor on 20 Sep 2013

You should correct the test suite. 1 isn't a prime number.

Vishal on 6 Oct 2014

Correct the test suite 1 is not prime number.

Daniel Pereira on 6 May 2016

1 is not a prime number, in order to fulfill with the fundamental theorem of arithmetic:

https://en.wikipedia.org/wiki/Fundamental_theorem_of_arithmetic

https://en.wikipedia.org/wiki/Prime_number#Primality_of_one

John D'Errico on 22 Feb 2018

I removed the test case where n==2, since 1 is indeed not a prime number. I also added a random test case, so the problem is not so easily cooked by knowing all the test cases.

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Problem 981. Find nearest prime number less than input number

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Problem 981. Find nearest prime number less than input number

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