Does $n = 2p$ where $p$ is prime, have fewer prime pairs than $n neq 2p?$











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Does an even integer $n = 2p$ where $p$ is prime, have relatively fewer prime pairs $(p_1, p_2)$ such that $p_1 + p_2 = n$, than an even integer $n neq 2p$?










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    Presumably you are comparing with $n$ twice a composite number
    – Henry
    yesterday










  • It's more a matter of how large $n$ is. Suppose $p = 7$, then $n = 14$ and you just have 3 + 11 = 7 + 7. Suppose instead $n = 720$, which is twice 360, clearly not a prime. You have 709 + 11 = 701 + 19 = 691 + 29 = 683 + 37 = 677 + 43 = etc.
    – Robert Soupe
    yesterday















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Does an even integer $n = 2p$ where $p$ is prime, have relatively fewer prime pairs $(p_1, p_2)$ such that $p_1 + p_2 = n$, than an even integer $n neq 2p$?










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  • 1




    Presumably you are comparing with $n$ twice a composite number
    – Henry
    yesterday










  • It's more a matter of how large $n$ is. Suppose $p = 7$, then $n = 14$ and you just have 3 + 11 = 7 + 7. Suppose instead $n = 720$, which is twice 360, clearly not a prime. You have 709 + 11 = 701 + 19 = 691 + 29 = 683 + 37 = 677 + 43 = etc.
    – Robert Soupe
    yesterday













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Does an even integer $n = 2p$ where $p$ is prime, have relatively fewer prime pairs $(p_1, p_2)$ such that $p_1 + p_2 = n$, than an even integer $n neq 2p$?










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Does an even integer $n = 2p$ where $p$ is prime, have relatively fewer prime pairs $(p_1, p_2)$ such that $p_1 + p_2 = n$, than an even integer $n neq 2p$?







prime-numbers






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edited yesterday









Robert Soupe

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  • 1




    Presumably you are comparing with $n$ twice a composite number
    – Henry
    yesterday










  • It's more a matter of how large $n$ is. Suppose $p = 7$, then $n = 14$ and you just have 3 + 11 = 7 + 7. Suppose instead $n = 720$, which is twice 360, clearly not a prime. You have 709 + 11 = 701 + 19 = 691 + 29 = 683 + 37 = 677 + 43 = etc.
    – Robert Soupe
    yesterday














  • 1




    Presumably you are comparing with $n$ twice a composite number
    – Henry
    yesterday










  • It's more a matter of how large $n$ is. Suppose $p = 7$, then $n = 14$ and you just have 3 + 11 = 7 + 7. Suppose instead $n = 720$, which is twice 360, clearly not a prime. You have 709 + 11 = 701 + 19 = 691 + 29 = 683 + 37 = 677 + 43 = etc.
    – Robert Soupe
    yesterday








1




1




Presumably you are comparing with $n$ twice a composite number
– Henry
yesterday




Presumably you are comparing with $n$ twice a composite number
– Henry
yesterday












It's more a matter of how large $n$ is. Suppose $p = 7$, then $n = 14$ and you just have 3 + 11 = 7 + 7. Suppose instead $n = 720$, which is twice 360, clearly not a prime. You have 709 + 11 = 701 + 19 = 691 + 29 = 683 + 37 = 677 + 43 = etc.
– Robert Soupe
yesterday




It's more a matter of how large $n$ is. Suppose $p = 7$, then $n = 14$ and you just have 3 + 11 = 7 + 7. Suppose instead $n = 720$, which is twice 360, clearly not a prime. You have 709 + 11 = 701 + 19 = 691 + 29 = 683 + 37 = 677 + 43 = etc.
– Robert Soupe
yesterday










1 Answer
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1
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This is just an attempt to understand the question which I think could be an interesting one but seems a little ill defined.



Define a set $S_m={ (p_1,p_2): p_1,p_2 in mathbb{P} text{ such that } 2m=p_1+p_2}$. Where $mathbb{P}$ is the set of primes.



Define a function $f(m)=|S_m|$.



So now we have some machinery in place. $f$ counts the number of ways we can write the double of a number as the sum of two primes. For example
$f(7)=3$ because we can write $14$ in $3$ different ways. $14=11+3=7+7=3+11$.



Note that you may decide not to count them in this way but if that's the case you should really specify how you want to count this in your question...



$f(6)=2$, because $12=5+7=7+5$.



$f(8)=4$, because $16= 5+11=11+5= 3+13=13+3$.



So we have $f(6)<f(7)<f(8)$.



Now after we build up some machinery... what's a good way to frame the question?



Something like this?



Maybe let $operatorname{avg}(n) = frac{1}{n}sum^n_{j=1} f(j)$



and let $operatorname{avg_p}(n) = frac{1}{pi(n)}sum^n_{p in mathbb{P}} f(p)$



Where $pi(n)$ is the number of primes less than $n$.



Then we can ask how these functions compare as $n$ grows?



Anyway... I think that this is one reasonable interpretation of this question but I am just trying to make the point that there are probably many possible interpretations you could ask. You might have to do some thinking about how to formulate this question so there is something to really investigate and not leave so much interpretation up to others...






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  • Thank you for your reply. Your interpretation of what I wanted to say is quite accurate. I apologize that my math and writing skills need work. Anyway, what I wanted to know is, if you graph f(x) where x is not prime, and you graph f(p) where p is prime, will the curve for f(x) always lie above f(p)?
    – temp watts
    yesterday













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1 Answer
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active

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1 Answer
1






active

oldest

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active

oldest

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active

oldest

votes








up vote
1
down vote













This is just an attempt to understand the question which I think could be an interesting one but seems a little ill defined.



Define a set $S_m={ (p_1,p_2): p_1,p_2 in mathbb{P} text{ such that } 2m=p_1+p_2}$. Where $mathbb{P}$ is the set of primes.



Define a function $f(m)=|S_m|$.



So now we have some machinery in place. $f$ counts the number of ways we can write the double of a number as the sum of two primes. For example
$f(7)=3$ because we can write $14$ in $3$ different ways. $14=11+3=7+7=3+11$.



Note that you may decide not to count them in this way but if that's the case you should really specify how you want to count this in your question...



$f(6)=2$, because $12=5+7=7+5$.



$f(8)=4$, because $16= 5+11=11+5= 3+13=13+3$.



So we have $f(6)<f(7)<f(8)$.



Now after we build up some machinery... what's a good way to frame the question?



Something like this?



Maybe let $operatorname{avg}(n) = frac{1}{n}sum^n_{j=1} f(j)$



and let $operatorname{avg_p}(n) = frac{1}{pi(n)}sum^n_{p in mathbb{P}} f(p)$



Where $pi(n)$ is the number of primes less than $n$.



Then we can ask how these functions compare as $n$ grows?



Anyway... I think that this is one reasonable interpretation of this question but I am just trying to make the point that there are probably many possible interpretations you could ask. You might have to do some thinking about how to formulate this question so there is something to really investigate and not leave so much interpretation up to others...






share|cite|improve this answer























  • Thank you for your reply. Your interpretation of what I wanted to say is quite accurate. I apologize that my math and writing skills need work. Anyway, what I wanted to know is, if you graph f(x) where x is not prime, and you graph f(p) where p is prime, will the curve for f(x) always lie above f(p)?
    – temp watts
    yesterday

















up vote
1
down vote













This is just an attempt to understand the question which I think could be an interesting one but seems a little ill defined.



Define a set $S_m={ (p_1,p_2): p_1,p_2 in mathbb{P} text{ such that } 2m=p_1+p_2}$. Where $mathbb{P}$ is the set of primes.



Define a function $f(m)=|S_m|$.



So now we have some machinery in place. $f$ counts the number of ways we can write the double of a number as the sum of two primes. For example
$f(7)=3$ because we can write $14$ in $3$ different ways. $14=11+3=7+7=3+11$.



Note that you may decide not to count them in this way but if that's the case you should really specify how you want to count this in your question...



$f(6)=2$, because $12=5+7=7+5$.



$f(8)=4$, because $16= 5+11=11+5= 3+13=13+3$.



So we have $f(6)<f(7)<f(8)$.



Now after we build up some machinery... what's a good way to frame the question?



Something like this?



Maybe let $operatorname{avg}(n) = frac{1}{n}sum^n_{j=1} f(j)$



and let $operatorname{avg_p}(n) = frac{1}{pi(n)}sum^n_{p in mathbb{P}} f(p)$



Where $pi(n)$ is the number of primes less than $n$.



Then we can ask how these functions compare as $n$ grows?



Anyway... I think that this is one reasonable interpretation of this question but I am just trying to make the point that there are probably many possible interpretations you could ask. You might have to do some thinking about how to formulate this question so there is something to really investigate and not leave so much interpretation up to others...






share|cite|improve this answer























  • Thank you for your reply. Your interpretation of what I wanted to say is quite accurate. I apologize that my math and writing skills need work. Anyway, what I wanted to know is, if you graph f(x) where x is not prime, and you graph f(p) where p is prime, will the curve for f(x) always lie above f(p)?
    – temp watts
    yesterday















up vote
1
down vote










up vote
1
down vote









This is just an attempt to understand the question which I think could be an interesting one but seems a little ill defined.



Define a set $S_m={ (p_1,p_2): p_1,p_2 in mathbb{P} text{ such that } 2m=p_1+p_2}$. Where $mathbb{P}$ is the set of primes.



Define a function $f(m)=|S_m|$.



So now we have some machinery in place. $f$ counts the number of ways we can write the double of a number as the sum of two primes. For example
$f(7)=3$ because we can write $14$ in $3$ different ways. $14=11+3=7+7=3+11$.



Note that you may decide not to count them in this way but if that's the case you should really specify how you want to count this in your question...



$f(6)=2$, because $12=5+7=7+5$.



$f(8)=4$, because $16= 5+11=11+5= 3+13=13+3$.



So we have $f(6)<f(7)<f(8)$.



Now after we build up some machinery... what's a good way to frame the question?



Something like this?



Maybe let $operatorname{avg}(n) = frac{1}{n}sum^n_{j=1} f(j)$



and let $operatorname{avg_p}(n) = frac{1}{pi(n)}sum^n_{p in mathbb{P}} f(p)$



Where $pi(n)$ is the number of primes less than $n$.



Then we can ask how these functions compare as $n$ grows?



Anyway... I think that this is one reasonable interpretation of this question but I am just trying to make the point that there are probably many possible interpretations you could ask. You might have to do some thinking about how to formulate this question so there is something to really investigate and not leave so much interpretation up to others...






share|cite|improve this answer














This is just an attempt to understand the question which I think could be an interesting one but seems a little ill defined.



Define a set $S_m={ (p_1,p_2): p_1,p_2 in mathbb{P} text{ such that } 2m=p_1+p_2}$. Where $mathbb{P}$ is the set of primes.



Define a function $f(m)=|S_m|$.



So now we have some machinery in place. $f$ counts the number of ways we can write the double of a number as the sum of two primes. For example
$f(7)=3$ because we can write $14$ in $3$ different ways. $14=11+3=7+7=3+11$.



Note that you may decide not to count them in this way but if that's the case you should really specify how you want to count this in your question...



$f(6)=2$, because $12=5+7=7+5$.



$f(8)=4$, because $16= 5+11=11+5= 3+13=13+3$.



So we have $f(6)<f(7)<f(8)$.



Now after we build up some machinery... what's a good way to frame the question?



Something like this?



Maybe let $operatorname{avg}(n) = frac{1}{n}sum^n_{j=1} f(j)$



and let $operatorname{avg_p}(n) = frac{1}{pi(n)}sum^n_{p in mathbb{P}} f(p)$



Where $pi(n)$ is the number of primes less than $n$.



Then we can ask how these functions compare as $n$ grows?



Anyway... I think that this is one reasonable interpretation of this question but I am just trying to make the point that there are probably many possible interpretations you could ask. You might have to do some thinking about how to formulate this question so there is something to really investigate and not leave so much interpretation up to others...







share|cite|improve this answer














share|cite|improve this answer



share|cite|improve this answer








edited yesterday

























answered yesterday









Mason

1,6501325




1,6501325












  • Thank you for your reply. Your interpretation of what I wanted to say is quite accurate. I apologize that my math and writing skills need work. Anyway, what I wanted to know is, if you graph f(x) where x is not prime, and you graph f(p) where p is prime, will the curve for f(x) always lie above f(p)?
    – temp watts
    yesterday




















  • Thank you for your reply. Your interpretation of what I wanted to say is quite accurate. I apologize that my math and writing skills need work. Anyway, what I wanted to know is, if you graph f(x) where x is not prime, and you graph f(p) where p is prime, will the curve for f(x) always lie above f(p)?
    – temp watts
    yesterday


















Thank you for your reply. Your interpretation of what I wanted to say is quite accurate. I apologize that my math and writing skills need work. Anyway, what I wanted to know is, if you graph f(x) where x is not prime, and you graph f(p) where p is prime, will the curve for f(x) always lie above f(p)?
– temp watts
yesterday






Thank you for your reply. Your interpretation of what I wanted to say is quite accurate. I apologize that my math and writing skills need work. Anyway, what I wanted to know is, if you graph f(x) where x is not prime, and you graph f(p) where p is prime, will the curve for f(x) always lie above f(p)?
– temp watts
yesterday












temp watts is a new contributor. Be nice, and check out our Code of Conduct.










 

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