feat: add carmichael number checker

[Soptq]

This PR adds Carmichael number checker.

Pull Request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no API changes)
• Build-related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue Number: N/A

What is the new behavior?

• checking whether a bumber is a Carmichael number.
• all tests are passed.

Does this introduce a breaking change?

• Yes
• No

Other information

[0xLucqs]

add more tests this is a bit light

[Soptq]

add more tests this is a bit light

Thanks for the advice, more tests are added ;). Note that 561 is the smallest Carmichael number (later is 41041, which requires about 1 billion gas to check and is too time-consuming for testing).

[0xLucqs]

then is it really useful to have that function ?

[Soptq]

then is it really useful to have that function ?

Indeed. The complexity of this function is too high for a smart contract. I think if someone really wants to check if a given number is a carmichael number, he/she can simply hard-coded carmichael numbers into a list and check if the given number is inside the list.

I will close this PR due to the low practicality.