MathDB
IOQM 2023-24 P-30

Source:

September 3, 2023
IOQM

Problem Statement

Let d(m)d(m) denote the number of positive integer divisors of a positive integer mm. If rr is the number of integers n⩽2023n \leqslant 2023 for which ∑i=1nd(i)\sum_{i=1}^{n} d(i) is odd. , find the sum of digits of r.r.
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