great, I agree, your code should be short and fast at the same time.

why?

Should be fixed by the fork above.

Approved by someone

PHP fork:

• fixing broken ref. solution.
• add input string to fail message

should fix this issue.

In PHP random tests, "irtaq" or "qohnito" or "tonqikuko" expects to be true. Is that correct? Or a bug in author's solution.

done

Not sure if this should be best practice

fixed as of December 2023 (7 years ltr)

OP solved it, closing

Approved

python new test framework is required. updated in this fork

More of a logic problem than a coding challenge.

I think it's called numerical sequences in Math.

Nice!