Marinada '22

[lang=hr] Podskup $ A \subset \{ 1, 2, \cdots, 673673 \} $ nazivamo zanimljivim ako ne sadrži tri različita elementa $x,y,z$ takva da $x$ dijeli $y$ i $y$ dijeli $z$. Nađi koliko najviše elemenata može imati zanimljiv podskup $A$ [/lang] [lang=en] Subset $ A \subset \{ 1, 2, \cdots, 673673 \} $ is called "interesting" if it doesn't contain 3 different elements $x,y,z$ such that $x$ divides $y$ and $y$ divides $z$. Find the the largest number of elements that can an "intersting" subset of A contain. [/lang]