|
| |
|
|
A243959
|
|
Numbers k such that k^524288 + 1 is prime.
|
|
22
|
|
|
|
1, 75898, 341112, 356926, 475856, 1880370, 2061748, 2312092, 2733014, 2788032, 2877652, 2985036, 3214654
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
COMMENTS
|
Numbers k such that k^(2^j) + 1 is a generalized Fermat prime for j=19.
1880370 is a member, but its position is not yet known. - Jeppe Stig Nielsen, Jan 24 2018
PrimeGrid has now tested and double checked the necessary candidates to prove that 1880370 is a(6). - Jeppe Stig Nielsen, Feb 20 2018
|
|
|
LINKS
|
Table of n, a(n) for n=1..13.
C. Caldwell, The largest known primes (Primes with 600,000 or more digits)
H. Dubner and Y. Gallot, Distribution of generalized Fermat prime numbers, Math. Comp., 71 (2002), 825-832.
J. S. S. Nielsen, Generalized Fermat Primes sorted by base (See table at the bottom of the page.)
PrimeGrid, Announcement of n=75898
PrimeGrid, Announcement of n=341112
PrimeGrid, Announcement of n=356926
PrimeGrid, Announcement of n=475856
PrimeGrid, Announcement of n=1880370
PrimeGrid, Announcement of n=2061748
PrimeGrid, Announcement of n=2312092
PrimeGrid, GFN Prime Search Status and History
PrimeGrid, PrimeGrid Primes - (GFN524288) Generalized Fermat Prime Search n=524288
|
|
|
PROG
|
(PARI) is(n)=isprime(n^524288+1) \\ Charles R Greathouse IV, Feb 20 2017
|
|
|
CROSSREFS
|
Cf. A056993, A005574, A000068, A006314, A006313, A006315, A006316, A056994, A056995, A057465, A057002, A088361, A088362, A226528, A226529, A226530, A251597, A253854, A244150, A321323.
Sequence in context: A323025 A323804 A135209 * A236807 A251470 A091294
Adjacent sequences: A243956 A243957 A243958 * A243960 A243961 A243962
|
|
|
KEYWORD
|
nonn,hard,more
|
|
|
AUTHOR
|
Felix Fröhlich, Jun 16 2014
|
|
|
EXTENSIONS
|
a(6) from Jeppe Stig Nielsen, Feb 20 2018
a(7) from Jeppe Stig Nielsen, Apr 27 2018
a(1) = 1 inserted and a(8) added by Jeppe Stig Nielsen, Sep 10 2018
a(9)-a(12) from Jeppe Stig Nielsen, Sep 21 2019
a(13) from Jeppe Stig Nielsen, Dec 27 2019
|
|
|
STATUS
|
approved
|
| |
|
|
