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Tool to test / find / check co-prime numbers. Two (or more) Integers are called coprimes if their GCD (greatest common divisor) is equal to 1.

Answers to Questions

What are coprimes? (Definition)

Prime numbers between them are numbers that share no common divisor (except 1).

Example: The number 4 has 1, 2 and 4 as divisors The number 9 has 1, 3 and 9 as divisors They share 1 as the only common divisor and so are coprimes.

How to calculate if numbers are coprimes?

Two numbers are coprimes if the GCD (greatest common divisor) of these numbers is equal to 1. This definition can be extended to N numbers.

Example: GCD(4,6) = 2, then 4 and 6 are not coprimes.

Example: GCD (4,5,6) = 1 then 4, 5 and 6 are coprimes (even if 4 and 6 are not).

Example: GCD (7,12) = 1 then 7 and 12 are coprimes.

How to find a coprime number with another?

dCode tests numbers depending on the prime factor decomposition of the first number (and therefore its divisors) to find coprime numbers. Then check that GCD equals 1 to confirm the number.

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Source code

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