Primes: 2 + 3 = 5, 3 + 5 = 8 (almost prime), 5 + 7 = 12 (11, 13 are prime), 7 + 11 = 18 (close to a prime)...











up vote
-2
down vote

favorite












My apologies if this happens to be a duplicate. I have no understanding on how to effectively search for these things (I am a programmer with way too little understanding of math, besides graph theory that is). Nevertheless, I'm curious about the following.



Here are the first couple of prime numbers (list dump): 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199.



I've noticed that when I sum two primes such that I traverse the list as follows:



2 + 3
3 + 5
5 + 7
7 + 11
11 + 13
13 + 17


The answer is always close to a prime (it either: is a prime, n-1 is a prime or n+1 is a prime). I don't know if this property holds forever but if it does, why?



As you can see by the way I'm asking this question: I'm interested in math but a bit scared (and unequipped) to gracefully deal with notation. So I'd really appreciate search terms that I could use on Google to look up all the definitions, the scavenger hunt for the right terms is real.



Thanks!










share|cite|improve this question




















  • 4




    There are a lot of small primes...it's not a great idea to search for patterns only for very small primes. If, randomly, we look at $101+103=204$ we see that the nearest primes are $199,211$. Just for one example.
    – lulu
    Nov 18 at 11:02






  • 2




    @Melvin Roest: Is $7+11=24$?
    – Yadati Kiran
    Nov 18 at 11:03










  • @Yadati Kiran: Wow... sorry. That was a huge oversight.
    – Melvin Roest
    Nov 18 at 11:12












  • @lulu: I suppose that's the answer then. Don't look for patterns by using small primes.
    – Melvin Roest
    Nov 18 at 11:13








  • 1




    Yes, that's right. There are so many small primes that it is very easy to imagine all sorts of patterns.
    – lulu
    Nov 18 at 11:14















up vote
-2
down vote

favorite












My apologies if this happens to be a duplicate. I have no understanding on how to effectively search for these things (I am a programmer with way too little understanding of math, besides graph theory that is). Nevertheless, I'm curious about the following.



Here are the first couple of prime numbers (list dump): 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199.



I've noticed that when I sum two primes such that I traverse the list as follows:



2 + 3
3 + 5
5 + 7
7 + 11
11 + 13
13 + 17


The answer is always close to a prime (it either: is a prime, n-1 is a prime or n+1 is a prime). I don't know if this property holds forever but if it does, why?



As you can see by the way I'm asking this question: I'm interested in math but a bit scared (and unequipped) to gracefully deal with notation. So I'd really appreciate search terms that I could use on Google to look up all the definitions, the scavenger hunt for the right terms is real.



Thanks!










share|cite|improve this question




















  • 4




    There are a lot of small primes...it's not a great idea to search for patterns only for very small primes. If, randomly, we look at $101+103=204$ we see that the nearest primes are $199,211$. Just for one example.
    – lulu
    Nov 18 at 11:02






  • 2




    @Melvin Roest: Is $7+11=24$?
    – Yadati Kiran
    Nov 18 at 11:03










  • @Yadati Kiran: Wow... sorry. That was a huge oversight.
    – Melvin Roest
    Nov 18 at 11:12












  • @lulu: I suppose that's the answer then. Don't look for patterns by using small primes.
    – Melvin Roest
    Nov 18 at 11:13








  • 1




    Yes, that's right. There are so many small primes that it is very easy to imagine all sorts of patterns.
    – lulu
    Nov 18 at 11:14













up vote
-2
down vote

favorite









up vote
-2
down vote

favorite











My apologies if this happens to be a duplicate. I have no understanding on how to effectively search for these things (I am a programmer with way too little understanding of math, besides graph theory that is). Nevertheless, I'm curious about the following.



Here are the first couple of prime numbers (list dump): 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199.



I've noticed that when I sum two primes such that I traverse the list as follows:



2 + 3
3 + 5
5 + 7
7 + 11
11 + 13
13 + 17


The answer is always close to a prime (it either: is a prime, n-1 is a prime or n+1 is a prime). I don't know if this property holds forever but if it does, why?



As you can see by the way I'm asking this question: I'm interested in math but a bit scared (and unequipped) to gracefully deal with notation. So I'd really appreciate search terms that I could use on Google to look up all the definitions, the scavenger hunt for the right terms is real.



Thanks!










share|cite|improve this question















My apologies if this happens to be a duplicate. I have no understanding on how to effectively search for these things (I am a programmer with way too little understanding of math, besides graph theory that is). Nevertheless, I'm curious about the following.



Here are the first couple of prime numbers (list dump): 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199.



I've noticed that when I sum two primes such that I traverse the list as follows:



2 + 3
3 + 5
5 + 7
7 + 11
11 + 13
13 + 17


The answer is always close to a prime (it either: is a prime, n-1 is a prime or n+1 is a prime). I don't know if this property holds forever but if it does, why?



As you can see by the way I'm asking this question: I'm interested in math but a bit scared (and unequipped) to gracefully deal with notation. So I'd really appreciate search terms that I could use on Google to look up all the definitions, the scavenger hunt for the right terms is real.



Thanks!







prime-numbers






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Nov 18 at 11:12

























asked Nov 18 at 10:45









Melvin Roest

1125




1125








  • 4




    There are a lot of small primes...it's not a great idea to search for patterns only for very small primes. If, randomly, we look at $101+103=204$ we see that the nearest primes are $199,211$. Just for one example.
    – lulu
    Nov 18 at 11:02






  • 2




    @Melvin Roest: Is $7+11=24$?
    – Yadati Kiran
    Nov 18 at 11:03










  • @Yadati Kiran: Wow... sorry. That was a huge oversight.
    – Melvin Roest
    Nov 18 at 11:12












  • @lulu: I suppose that's the answer then. Don't look for patterns by using small primes.
    – Melvin Roest
    Nov 18 at 11:13








  • 1




    Yes, that's right. There are so many small primes that it is very easy to imagine all sorts of patterns.
    – lulu
    Nov 18 at 11:14














  • 4




    There are a lot of small primes...it's not a great idea to search for patterns only for very small primes. If, randomly, we look at $101+103=204$ we see that the nearest primes are $199,211$. Just for one example.
    – lulu
    Nov 18 at 11:02






  • 2




    @Melvin Roest: Is $7+11=24$?
    – Yadati Kiran
    Nov 18 at 11:03










  • @Yadati Kiran: Wow... sorry. That was a huge oversight.
    – Melvin Roest
    Nov 18 at 11:12












  • @lulu: I suppose that's the answer then. Don't look for patterns by using small primes.
    – Melvin Roest
    Nov 18 at 11:13








  • 1




    Yes, that's right. There are so many small primes that it is very easy to imagine all sorts of patterns.
    – lulu
    Nov 18 at 11:14








4




4




There are a lot of small primes...it's not a great idea to search for patterns only for very small primes. If, randomly, we look at $101+103=204$ we see that the nearest primes are $199,211$. Just for one example.
– lulu
Nov 18 at 11:02




There are a lot of small primes...it's not a great idea to search for patterns only for very small primes. If, randomly, we look at $101+103=204$ we see that the nearest primes are $199,211$. Just for one example.
– lulu
Nov 18 at 11:02




2




2




@Melvin Roest: Is $7+11=24$?
– Yadati Kiran
Nov 18 at 11:03




@Melvin Roest: Is $7+11=24$?
– Yadati Kiran
Nov 18 at 11:03












@Yadati Kiran: Wow... sorry. That was a huge oversight.
– Melvin Roest
Nov 18 at 11:12






@Yadati Kiran: Wow... sorry. That was a huge oversight.
– Melvin Roest
Nov 18 at 11:12














@lulu: I suppose that's the answer then. Don't look for patterns by using small primes.
– Melvin Roest
Nov 18 at 11:13






@lulu: I suppose that's the answer then. Don't look for patterns by using small primes.
– Melvin Roest
Nov 18 at 11:13






1




1




Yes, that's right. There are so many small primes that it is very easy to imagine all sorts of patterns.
– lulu
Nov 18 at 11:14




Yes, that's right. There are so many small primes that it is very easy to imagine all sorts of patterns.
– lulu
Nov 18 at 11:14















active

oldest

votes











Your Answer





StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














 

draft saved


draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3003374%2fprimes-2-3-5-3-5-8-almost-prime-5-7-12-11-13-are-prime-7%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown






























active

oldest

votes













active

oldest

votes









active

oldest

votes






active

oldest

votes
















 

draft saved


draft discarded



















































 


draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3003374%2fprimes-2-3-5-3-5-8-almost-prime-5-7-12-11-13-are-prime-7%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Le Mesnil-Réaume

Ida-Boy-Ed-Garten

web3.py web3.isConnected() returns false always