Find out if a number has repetitive digits [formula homework]

Time for a quick formula finesse check. Let’s say you have a number in A1. What formula can you use to find out if it has duplicate digits.

For example, if A1 has 123405, then answer should be FALSE
and if A1 has 123455, then answer should be TRUE

Go ahead and post your answers (formulas, VBA or M script) in the comments section.

Clues and hints

Check out below formula tips to get some clues on how to solve this problem.

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