Prirodni broj
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je zanimljiv ako je
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neparan. Odredi sumu svih zanimljivih brojeva.
Positive integer
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is interesting if
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is odd. Calculate the sum of all interesting numbers.
[lang=hr]
Prirodni broj $n$ je zanimljiv ako je $\varphi(n)$ neparan. Odredi sumu svih zanimljivih brojeva.
[/lang]
[lang=en]
Positive integer $n$ is interesting if $\varphi(n)$ is odd. Calculate the sum of all interesting numbers.
[/lang]