78 questions linked to/from Is this number a prime?
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### What's the time, chap?

I honestly cannot believe that this is not a question yet on Code Golf, but.... Print the local time (with a.m. or p.m.) as a string to the console, preceded by "It's ". Example: ...
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### Primes with prime bit-counts

Task Find all the non-negative integers up to and including a given non-zero positive integer n, that are prime and the count of 1's and ...
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### Tips for Creating/Maintaining a Golfing Language

Creating a golfing language can be hard. Let's help budding golfing language creators out and provide some helpful tips on how to create one. I'm looking for tips on: The design process ...
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### Is this a Smith number?

Challenge description A Smith number is a composite number whose sum of digits is equal to the sum of sums of digits of its prime factors. Given an integer N, ...
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### Print the nth prime that contains n

This question will be a twist on finding the nth prime number. Challenge You must write a program that will take one input n, ...
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### Magnanimous numbers

Given an positive integer as input determine if it is a magnanimous number. A magnanimous number is a number such that any insertion of a + sign between any two ...
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### List Prime Numbers [duplicate]

Introduction Prime numbers are simple, right? Well, now you get your chance to find out! Challenge You must write a program or function that takes an input n and ...
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### The program that will find the next prime number

Intro: You accidentally corrupted the flow of time with a device you made for fun, that turned out to be a time machine. As a result, you got pushed to the far future. You realized that computing, ...
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### Get thee behind me Satan-Prime!

Satan-Primes who are they? they are Primes containing 666 these are Satan-Primes:...
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### It almost works (Cops' Thread)

Robbers' Thread Your challenge is to find an existing challenge, and implement it in a way such that certain inputs fail. At least one input must not produce the correct output (use the other ...
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### Generate Sexy Primes

Sexy Primes are pairs of numbers $(n, n+6)$ such as $n$ and $n+6$ are both prime You need to create a function which will take an integer, check for sexy primes from 0 to that integer, and ...
• 263
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### Prime parity peregrination

The purpose of this challenge is to graphically depict a walk on the plane, where the direction of each step $k$ is determined by the primality of $k$ and the parity of its binary expansion. ...
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### Cops and Robbers: Redacted Primality (Cops' Thread)

This challenge was originally sandboxed by Magic Octopus Urn; I adopted and posted it with his permission. This is the cops' thread. The robbers' thread is here. The challenge Step One: Write a ...
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### Finding Not-Quite-Prime Numbers

Your challenge, should you chose to accept it, is to code-golf a function that returns true or false (or some similar meaningful representation of yes and no) if a number meets the following criteria: ...
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