[thesz]

Some of them, with notable exception of perfect squares of primes, can be expressed by products of different combinations of factors.

E.g., 6^2 = (223)3 = 2(233).

One of ~22 (ln(2^32)) perfect squares will be a square of perfect prime. Most won't.

[mkl]

Decoding this so it's readable: 6^2 = (2*2*3)*3 = 2*(2*3*3).

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