Let G be the directed graph whose vertices are the integers (2, 3,... N). A directed edge goes from a to b if b/a is an integer

Question

Let G be the directed graph whose vertices are the integers (2, 3,... N). A directed edge goes from a to b if b/a is an integer greater than 1.
Which is the smallest given N so that some vertex in G has in-degree at least 6?
12
16
30
35
I need to learn this.

Kunduz · Accepted Answer

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