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Number TheorySuperchallengeFactors & Multiples

Factors & Multiples · Superchallenge problem

Take N=24⋅33⋅52N = 2^4\cdot3^3\cdot5^2. Count the chains d∣e∣Nd \mid e \mid N in which dd and ee are positive integers (d=ed = e and e=Ne = N are allowed).