Wolfram Function Repository
Instantuse addon functions for the Wolfram Language
Function Repository Resource:
Obtain a certificate showing that a number is prime or composite
ResourceFunction["PrimeQCertificate"][n] gives a certificate that n is prime or that n is composite. 
A certificate that can be used to prove that 1093 is a prime:
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The same certificate can be obtained by using ProvablePrimeQ with the option "Certificate"→True:
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A certificate that can be used to prove that 1093 × 3511 is composite:
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The output is a list of three integers that indicate 1093 × 3511 is composite, and that it violates Fermat's little theorem for primes, 2^{p1}≡1mod p if p is prime:
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Wolfram Language 11.3 (March 2018) or above
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