Is Every Positive Integer Divisible by 2, 3, or 5?

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The discussion centers on the divisibility of positive integers by 2, 3, and 5, with the assertion that the sum of fractions representing these divisibilities converges to 1. The user outlines a method to calculate the proportions of integers divisible by these numbers, specifically detailing the fractions for each case. The mathematical notation used indicates a deep exploration of number theory, particularly in relation to prime numbers and their divisibility properties.

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I really didn't know how to word the title so sorry if it's a little confusing.
And I didn't know whether to post this in number theory or not but ah well.

The other day, I started thinking about this and I was just wondering if it had been done before or if it's even correct;

Half of all positive integers are divisible by 2,
A third are divisible by 3,
A quarter by 4 etc.

Now, of the third that are divisible by 3, a half of those numbers are also divisible by 2.
So 1/6 of positive integers are divisible by 3 and not 2.

I continued this trend to find;
[tex]\frac{1}{2}[/tex] of p. ints are divisible by 2
[tex]\frac{1}{3}\left(1-\frac{1}{2}\right)[/tex] are divisible by 3 and not 2
[tex]\frac{1}{5}\left(1-\left(\frac{1}{2}+\frac{1}{3}\left(1-\frac{1}{2}\right)\right)\right)[/tex] are divisible by 5 and not 3 or 2
[tex]\frac{1}{7}\left(1-\left(\frac{1}{2}+\frac{1}{3}\left(1-\frac{1}{2}\right)+\frac{1}{5}\left(1-\left(\frac{1}{2}+\frac{1}{3}\left(1-\frac{1}{2}\right)\right)\right)\right)\right)[/tex] are divisible by 7 and not 5, 3 or 2

If I sum all these to infinity, it should equal 1 as it will then cover all positive integers.

So could you by any chance verify the truth of this statement,

[tex]\sum^{\infty}_{p_{0}=2}\frac{1}{p_{0}}\left(1-\sum^{p_{0}-1}_{p_{1}=2}\frac{1}{p_{1}}\left(1-\sum^{p_{1}-1}_{p_{2}=2}\frac{1}{p_{2}}\left(...\right)\right)\right) = 1[/tex]

I know this is quite awkward looking and I don't even know if I've used correct notation, I just sort of scrawled it down as I was thinking it.
 
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To make it a little easier: the sum of "divisible by 2" + "not divisible by 2 but divisible by 3" + "not divisible by 2 or 3 but divisible by 5" is "divisible by 2, 3, or 5" which is "not relatively prime to 2, 3, and 5":

[tex]f_1 = 1/2[/tex]
[tex]f_2 = 1/2 + 1/2\cdot1/3 = 1 - 1/2\cdot2/3[/tex]
[tex]f_3 = 1/2 + 1/2\cdot1/3 + 1/2\cdot2/3\cdot1/5 = 1 - 1/2\cdot2/3\cdot4/5[/tex]
. . .
[tex]f_k = 1 - \sum_{q\in\mathbb{P},q\le p_k}\left(1-\frac1p\right)[/tex]

Now instead of lots of sums, you only have one. All you need to show is that the sum in question tends to 0 as k goes to infinity (which is true).
 

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