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ace_loves_xq's blog

By ace_loves_xq, history, 4 years ago, In English

Given parameters a,b,c; max(a,b,c)9000. Your task is to compute ax=1by=1cz=1d(xyz) by modulo 230 where d(n) is the divisor count function : the number of positive divisors of n.

This is the final problem in my recent OI Mocktest, I can only solve it to the first subtask: max(a,b,c)200, by iterating over all triplets (x,y,z) and adding d(xyz) to the result variable, to compute d(xyz), I used applied prime sieve.

Can you suggest the algorithm for the final subtask?

Any help would be highly appreciated!

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