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Deficiency 128

Min_25 · Math · 2018-08-28

Let S(N) be the sum of n (1≤n≤N) such that σ(n)−2n=−128, where σ(n) is the sum of divisors function.

For example, S(107)=11033992.

Find S(1015).

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Problem preserved from RoseCode, with formatting adapted for this archive. CC BY-NC-SA 4.0

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