Wolfram Function Repository
Instantuse addon functions for the Wolfram Language
Function Repository Resource:
Find all overlapfree strings of a specified length
ResourceFunction["OverlapFreeStringTuples"][n] gives strings composed of two characters with lengths up to n that do not self overlap.  
ResourceFunction["OverlapFreeStringTuples"][k,n] gives strings composed of k characters with lengths up to n that do not self overlap.  
ResourceFunction["OverlapFreeStringTuples"][k,n,s] gives stuples of strings of k characters with lengths up to n that do not overlap themselves or each other. 
Find overlapfree strings with lengths up to 5:
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Find overlapfree strings with lengths up to 4 and a 3letter alphabet:
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Find overlapfree pairs of strings with 2letter alphabets and lengths up to 5:
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There are no triples of nonoverlapping strings up to length 5:
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At length 6, there are overlapfree triples of strings:
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