Three of them.
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There are four pair of mirror primes.
There 25 primes less than 100: 2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97.
All pairs of two primes are coprime. There are fifteen primes under 50. So that means there are 105 unique pairs of "coprime primes", or more generally, pairs of primes, under 50.
One pair of twin primes between 135 and 145
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