Tool to test / find / check co-prime numbers (relatively prime). Two (or more) Integers are called coprimes if their GCD (greatest common divisor) is equal to 1.
Coprimes - dCode
Tag(s) : Arithmetics
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Coprimes
Coprime Checker
Coprime Number Finder
Answers to Questions (FAQ)
What are coprimes/relatively primes numbers? (Definition)
How to calculate if numbers are coprimes?
Formally, in mathematics, 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 (pairwise).
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, but not pairwise coprime as 4 and 6 are not relatively primes.
Example: GCD (7,12) = 1 then 7 and 12 are coprimes.
How to prove that 2 numbers are coprimes?
For two numbers a and b, Calculate the GCD(a,b) of the 2 numbers, if it is equal to 1 then the 2 numbers a and b are relatively primes.
How to find a coprime number with another?
dCode's calculator/checker 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.
See also the Euler Totient or the primality tests.
How to check coprime numbers with a calculator?
Some calculators have the coprime() function or use the gcd() function and check that the value is 1.
Are 1 and 1 coprimes?
According to the definition, yes, 1 and 1 are coprimes as GCD(1,1)=1. Moreover 1 and any positive integer are relatively primes.
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