java - Fast factoring algorithms? -

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how can find factors of number?

e.g.:

digit: 20
factors: {1*20, 2*10, 4*5, 5*4, 10*2, 20*1}

this problem no solution known. reason, rsa encryption depends on computational difficulty of factoring numbers. see: integer factorization

however, may able speed algorithms given looking @ numbers square root of n, , checking if factors checking if n % == 0. if true, can find corresponding factor greater n^(.5) taking n / i.


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