Currently there may be errors shown on top of a page, because of a missing Wiki update (PHP version and extension DPL3). |
Navigation
Topics | Help • Register • News • History • How to • Sequences statistics • Template prototypes |
Difference between revisions of "Liskovets-Gallot conjectures"
(new) |
(link) |
||
Line 36: | Line 36: | ||
==Search== | ==Search== | ||
− | The current search is maintaind by the [[Conjectures 'R Us]] project and can be found [[here]]. | + | The current search is maintaind by the [[Conjectures 'R Us]] project and can be found [[CRUS Liskovets-Gallot|here]]. |
==Links== | ==Links== | ||
*[https://www.primepuzzles.net/problems/prob_036.htm Problem 36] "The Liskovets-Gallot numbers" from [https://www.primepuzzles.net/index.shtml PP&P connection] by [[Carlos Rivera]] | *[https://www.primepuzzles.net/problems/prob_036.htm Problem 36] "The Liskovets-Gallot numbers" from [https://www.primepuzzles.net/index.shtml PP&P connection] by [[Carlos Rivera]] | ||
[[Category:Math]] | [[Category:Math]] |
Revision as of 15:45, 5 July 2020
Contents
Definitions
Valery Liskovets studied the list of k•2n+1 primes and observed, that the k's (k divisible by 3) got an irregular contribution of odd and even exponents yielding a prime.
Examples: (for 1 <= n <= 100000)
k-value | # odd | # even |
---|---|---|
51 | 38 | 5 |
231 | 51 | 9 |
261 | 56 | 14 |
87 | 2 | 36 |
93 | 1 | 38 |
177 | 8 | 46 |
So Liskovets formulated the conjecture:
- "There exist k, 3|k, such that primes k•2n+1 do exist but only with odd n /only with even n."
Yves Gallot extended this for k•2n-1 numbers and gave also the first solutions as:
- k•2n+1 is composite for all n=even: k=66741
- k•2n+1 is composite for all n=odd: k=95283
- k•2n-1 is composite for all n=even: k=39939
- k•2n-1 is composite for all n=odd: k=172677
Proof
The verification of these conjectures has to be done in the same manner like the Riesel problem: find a prime for all k-values less than the given with the needed condition.
Search
The current search is maintaind by the Conjectures 'R Us project and can be found here.
Links
- Problem 36 "The Liskovets-Gallot numbers" from PP&P connection by Carlos Rivera