Is 31 the only number that can be represented by two distinct sums of consecutive powers of primes? [duplicate]

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  • On uniqueness of sums of prime powers

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I'm trying to prove that a number with two distinct prime factors can't be friends with another number with the same prime factors.



One way I could prove this is that there'd be only one example where $$sum_i=0^np^i=sum_j=0^mq^j$$



That example, preferrably, would be $2^0+2^1+2^2+2^3+2^4=5^0+5^1+5^2=31$, which fails to fit other conditions necessary to construct that pair of friends.



Through a little bit of computing power, I was unable to find examples for $p<300,n<10$, which leads me to believe it may be the only example. However, I'm completely lost on a continuation, if there is one, and whether this is just a case of the XY problem, and I should drop this line of reasoning and move elsewhere.







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marked as duplicate by Steven Stadnicki, Trần Thúc Minh Trí, max_zorn, Claude Leibovici, Parcly Taxel Jul 17 at 11:35


This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.










  • 1




    Possibly related: math.stackexchange.com/questions/2599653/…
    – Crostul
    Jul 15 at 6:54










  • Possibly related?!?! You mean: Is the exact same question?
    – Mason
    Jul 15 at 7:02










  • Oh shoot, I did my best to see if this already had an answer. I guess I was looking with the wrong terms and being overdescriptive with it. The Goormaghtigh conjecture certainly helped in the other question, so thanks.
    – Gelly
    Jul 15 at 17:05














up vote
0
down vote

favorite













This question already has an answer here:



  • On uniqueness of sums of prime powers

    1 answer



I'm trying to prove that a number with two distinct prime factors can't be friends with another number with the same prime factors.



One way I could prove this is that there'd be only one example where $$sum_i=0^np^i=sum_j=0^mq^j$$



That example, preferrably, would be $2^0+2^1+2^2+2^3+2^4=5^0+5^1+5^2=31$, which fails to fit other conditions necessary to construct that pair of friends.



Through a little bit of computing power, I was unable to find examples for $p<300,n<10$, which leads me to believe it may be the only example. However, I'm completely lost on a continuation, if there is one, and whether this is just a case of the XY problem, and I should drop this line of reasoning and move elsewhere.







share|cite|improve this question











marked as duplicate by Steven Stadnicki, Trần Thúc Minh Trí, max_zorn, Claude Leibovici, Parcly Taxel Jul 17 at 11:35


This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.










  • 1




    Possibly related: math.stackexchange.com/questions/2599653/…
    – Crostul
    Jul 15 at 6:54










  • Possibly related?!?! You mean: Is the exact same question?
    – Mason
    Jul 15 at 7:02










  • Oh shoot, I did my best to see if this already had an answer. I guess I was looking with the wrong terms and being overdescriptive with it. The Goormaghtigh conjecture certainly helped in the other question, so thanks.
    – Gelly
    Jul 15 at 17:05












up vote
0
down vote

favorite









up vote
0
down vote

favorite












This question already has an answer here:



  • On uniqueness of sums of prime powers

    1 answer



I'm trying to prove that a number with two distinct prime factors can't be friends with another number with the same prime factors.



One way I could prove this is that there'd be only one example where $$sum_i=0^np^i=sum_j=0^mq^j$$



That example, preferrably, would be $2^0+2^1+2^2+2^3+2^4=5^0+5^1+5^2=31$, which fails to fit other conditions necessary to construct that pair of friends.



Through a little bit of computing power, I was unable to find examples for $p<300,n<10$, which leads me to believe it may be the only example. However, I'm completely lost on a continuation, if there is one, and whether this is just a case of the XY problem, and I should drop this line of reasoning and move elsewhere.







share|cite|improve this question












This question already has an answer here:



  • On uniqueness of sums of prime powers

    1 answer



I'm trying to prove that a number with two distinct prime factors can't be friends with another number with the same prime factors.



One way I could prove this is that there'd be only one example where $$sum_i=0^np^i=sum_j=0^mq^j$$



That example, preferrably, would be $2^0+2^1+2^2+2^3+2^4=5^0+5^1+5^2=31$, which fails to fit other conditions necessary to construct that pair of friends.



Through a little bit of computing power, I was unable to find examples for $p<300,n<10$, which leads me to believe it may be the only example. However, I'm completely lost on a continuation, if there is one, and whether this is just a case of the XY problem, and I should drop this line of reasoning and move elsewhere.





This question already has an answer here:



  • On uniqueness of sums of prime powers

    1 answer









share|cite|improve this question










share|cite|improve this question




share|cite|improve this question









asked Jul 15 at 6:51









Gelly

33




33




marked as duplicate by Steven Stadnicki, Trần Thúc Minh Trí, max_zorn, Claude Leibovici, Parcly Taxel Jul 17 at 11:35


This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.






marked as duplicate by Steven Stadnicki, Trần Thúc Minh Trí, max_zorn, Claude Leibovici, Parcly Taxel Jul 17 at 11:35


This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.









  • 1




    Possibly related: math.stackexchange.com/questions/2599653/…
    – Crostul
    Jul 15 at 6:54










  • Possibly related?!?! You mean: Is the exact same question?
    – Mason
    Jul 15 at 7:02










  • Oh shoot, I did my best to see if this already had an answer. I guess I was looking with the wrong terms and being overdescriptive with it. The Goormaghtigh conjecture certainly helped in the other question, so thanks.
    – Gelly
    Jul 15 at 17:05












  • 1




    Possibly related: math.stackexchange.com/questions/2599653/…
    – Crostul
    Jul 15 at 6:54










  • Possibly related?!?! You mean: Is the exact same question?
    – Mason
    Jul 15 at 7:02










  • Oh shoot, I did my best to see if this already had an answer. I guess I was looking with the wrong terms and being overdescriptive with it. The Goormaghtigh conjecture certainly helped in the other question, so thanks.
    – Gelly
    Jul 15 at 17:05







1




1




Possibly related: math.stackexchange.com/questions/2599653/…
– Crostul
Jul 15 at 6:54




Possibly related: math.stackexchange.com/questions/2599653/…
– Crostul
Jul 15 at 6:54












Possibly related?!?! You mean: Is the exact same question?
– Mason
Jul 15 at 7:02




Possibly related?!?! You mean: Is the exact same question?
– Mason
Jul 15 at 7:02












Oh shoot, I did my best to see if this already had an answer. I guess I was looking with the wrong terms and being overdescriptive with it. The Goormaghtigh conjecture certainly helped in the other question, so thanks.
– Gelly
Jul 15 at 17:05




Oh shoot, I did my best to see if this already had an answer. I guess I was looking with the wrong terms and being overdescriptive with it. The Goormaghtigh conjecture certainly helped in the other question, so thanks.
– Gelly
Jul 15 at 17:05










1 Answer
1






active

oldest

votes

















up vote
1
down vote



accepted










Nope!



$$sum_i=0^290^i=1+90+90^2=8191=1+2+2^2+2^3+dots +2^12=sum_j=0^122^j$$



As is mentioned in the comments this question is duplicate.






share|cite|improve this answer





















  • Whoops! The OP asks for primes! This $90$ doesn't do the trick.
    – Mason
    Jul 16 at 21:16

















1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes








up vote
1
down vote



accepted










Nope!



$$sum_i=0^290^i=1+90+90^2=8191=1+2+2^2+2^3+dots +2^12=sum_j=0^122^j$$



As is mentioned in the comments this question is duplicate.






share|cite|improve this answer





















  • Whoops! The OP asks for primes! This $90$ doesn't do the trick.
    – Mason
    Jul 16 at 21:16














up vote
1
down vote



accepted










Nope!



$$sum_i=0^290^i=1+90+90^2=8191=1+2+2^2+2^3+dots +2^12=sum_j=0^122^j$$



As is mentioned in the comments this question is duplicate.






share|cite|improve this answer





















  • Whoops! The OP asks for primes! This $90$ doesn't do the trick.
    – Mason
    Jul 16 at 21:16












up vote
1
down vote



accepted







up vote
1
down vote



accepted






Nope!



$$sum_i=0^290^i=1+90+90^2=8191=1+2+2^2+2^3+dots +2^12=sum_j=0^122^j$$



As is mentioned in the comments this question is duplicate.






share|cite|improve this answer













Nope!



$$sum_i=0^290^i=1+90+90^2=8191=1+2+2^2+2^3+dots +2^12=sum_j=0^122^j$$



As is mentioned in the comments this question is duplicate.







share|cite|improve this answer













share|cite|improve this answer



share|cite|improve this answer











answered Jul 15 at 7:14









Mason

1,2401224




1,2401224











  • Whoops! The OP asks for primes! This $90$ doesn't do the trick.
    – Mason
    Jul 16 at 21:16
















  • Whoops! The OP asks for primes! This $90$ doesn't do the trick.
    – Mason
    Jul 16 at 21:16















Whoops! The OP asks for primes! This $90$ doesn't do the trick.
– Mason
Jul 16 at 21:16




Whoops! The OP asks for primes! This $90$ doesn't do the trick.
– Mason
Jul 16 at 21:16


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