Prime factors of $2^{2^2}+3^{3^3}+5^{5^5}+7^{7^7}$












5












$begingroup$


Are there any useful restrictions to the prime factors of the number



$$2^{2^2}+3^{3^3}+5^{5^5}+7^{7^7}?$$



The two smallest are $6771419$ and $72153167$, which I found by trial division. The number is small enough for ECM, but this is quite slow for numbers
of this magnitude.



Is there anything better than trial division or ECM ?










share|cite|improve this question











$endgroup$








  • 2




    $begingroup$
    'The number is small enough for ECM' - this number is roughly 700K decimal digits; AFAIK that's still well out of reach of even the best general-purpose factoring methods...
    $endgroup$
    – Steven Stadnicki
    Feb 19 '14 at 23:17






  • 1




    $begingroup$
    For people like me who like W|A... it choked on this.
    $endgroup$
    – apnorton
    Feb 19 '14 at 23:35










  • $begingroup$
    Interestingly enough, the sum of the first two addends is prime. Yet I entirely fail to see how that helps you in any way. :)
    $endgroup$
    – apnorton
    Feb 20 '14 at 1:16
















5












$begingroup$


Are there any useful restrictions to the prime factors of the number



$$2^{2^2}+3^{3^3}+5^{5^5}+7^{7^7}?$$



The two smallest are $6771419$ and $72153167$, which I found by trial division. The number is small enough for ECM, but this is quite slow for numbers
of this magnitude.



Is there anything better than trial division or ECM ?










share|cite|improve this question











$endgroup$








  • 2




    $begingroup$
    'The number is small enough for ECM' - this number is roughly 700K decimal digits; AFAIK that's still well out of reach of even the best general-purpose factoring methods...
    $endgroup$
    – Steven Stadnicki
    Feb 19 '14 at 23:17






  • 1




    $begingroup$
    For people like me who like W|A... it choked on this.
    $endgroup$
    – apnorton
    Feb 19 '14 at 23:35










  • $begingroup$
    Interestingly enough, the sum of the first two addends is prime. Yet I entirely fail to see how that helps you in any way. :)
    $endgroup$
    – apnorton
    Feb 20 '14 at 1:16














5












5








5


3



$begingroup$


Are there any useful restrictions to the prime factors of the number



$$2^{2^2}+3^{3^3}+5^{5^5}+7^{7^7}?$$



The two smallest are $6771419$ and $72153167$, which I found by trial division. The number is small enough for ECM, but this is quite slow for numbers
of this magnitude.



Is there anything better than trial division or ECM ?










share|cite|improve this question











$endgroup$




Are there any useful restrictions to the prime factors of the number



$$2^{2^2}+3^{3^3}+5^{5^5}+7^{7^7}?$$



The two smallest are $6771419$ and $72153167$, which I found by trial division. The number is small enough for ECM, but this is quite slow for numbers
of this magnitude.



Is there anything better than trial division or ECM ?







number-theory prime-factorization tetration






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Dec 11 '18 at 14:55









Klangen

1,72811334




1,72811334










asked Feb 19 '14 at 23:08









PeterPeter

47.4k1039129




47.4k1039129








  • 2




    $begingroup$
    'The number is small enough for ECM' - this number is roughly 700K decimal digits; AFAIK that's still well out of reach of even the best general-purpose factoring methods...
    $endgroup$
    – Steven Stadnicki
    Feb 19 '14 at 23:17






  • 1




    $begingroup$
    For people like me who like W|A... it choked on this.
    $endgroup$
    – apnorton
    Feb 19 '14 at 23:35










  • $begingroup$
    Interestingly enough, the sum of the first two addends is prime. Yet I entirely fail to see how that helps you in any way. :)
    $endgroup$
    – apnorton
    Feb 20 '14 at 1:16














  • 2




    $begingroup$
    'The number is small enough for ECM' - this number is roughly 700K decimal digits; AFAIK that's still well out of reach of even the best general-purpose factoring methods...
    $endgroup$
    – Steven Stadnicki
    Feb 19 '14 at 23:17






  • 1




    $begingroup$
    For people like me who like W|A... it choked on this.
    $endgroup$
    – apnorton
    Feb 19 '14 at 23:35










  • $begingroup$
    Interestingly enough, the sum of the first two addends is prime. Yet I entirely fail to see how that helps you in any way. :)
    $endgroup$
    – apnorton
    Feb 20 '14 at 1:16








2




2




$begingroup$
'The number is small enough for ECM' - this number is roughly 700K decimal digits; AFAIK that's still well out of reach of even the best general-purpose factoring methods...
$endgroup$
– Steven Stadnicki
Feb 19 '14 at 23:17




$begingroup$
'The number is small enough for ECM' - this number is roughly 700K decimal digits; AFAIK that's still well out of reach of even the best general-purpose factoring methods...
$endgroup$
– Steven Stadnicki
Feb 19 '14 at 23:17




1




1




$begingroup$
For people like me who like W|A... it choked on this.
$endgroup$
– apnorton
Feb 19 '14 at 23:35




$begingroup$
For people like me who like W|A... it choked on this.
$endgroup$
– apnorton
Feb 19 '14 at 23:35












$begingroup$
Interestingly enough, the sum of the first two addends is prime. Yet I entirely fail to see how that helps you in any way. :)
$endgroup$
– apnorton
Feb 20 '14 at 1:16




$begingroup$
Interestingly enough, the sum of the first two addends is prime. Yet I entirely fail to see how that helps you in any way. :)
$endgroup$
– apnorton
Feb 20 '14 at 1:16










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