Nested Carmichael numbers - A generalization of the Korselt's criterion
Concerning Marcel Martin's post "Constructing Carmichael numbers" to YahooGroups primenumbers list,
I have discovered a generalization of the Korselt's criterion (1899) :
"A composite odd number n is a Carmichael number if and only if n is squarefree
and p-1 divides n-1 for every prime p dividing n"
Please have a look at my article "A generalization of the Korselt's criterion - Nested
Carmichael numbers" on :
Perhaps this could be useful for compression purposes.
I'm looking forward to your comments,
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