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sum of greatest odd divisors of n (HOMC 2019 JI-10)
sum of greatest odd divisors of n (HOMC 2019 JI-10)
Source:
November 7, 2020
number theory
divisor
odd
Sum
Problem Statement
For any positive integer
n
n
n
, let
r
n
r_n
r
n
denote the greatest odd divisor of
n
n
n
. Compute
T
=
r
100
+
r
101
+
r
102
+
.
.
.
+
r
200
T =r_{100}+ r_{101} + r_{102}+...+r_{200}
T
=
r
100
+
r
101
+
r
102
+
...
+
r
200
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