|
| |
|
|
A096305
|
|
Numbers n such that 7^n + 4 is prime.
|
|
11
|
|
|
|
0, 1, 2, 3, 5, 7, 9, 14, 23, 129, 198, 235, 275, 630, 870, 1033, 1290, 3293, 3458, 11466, 13885, 25893, 32186, 33139, 58125, 78929, 97197
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,3
|
|
|
COMMENTS
|
a(28) > 10^5. - Robert Price, Jan 24 2014
|
|
|
LINKS
|
Table of n, a(n) for n=1..27.
|
|
|
EXAMPLE
|
7^14 + 4 = 678223072853 is a prime number.
|
|
|
MATHEMATICA
|
Do[If[PrimeQ[7^n+4], Print[n]], {n, 1, 1000}]
|
|
|
PROG
|
(PARI) for(n=0, 10^5, if(ispseudoprime(7^n+4), print1(n, ", "))) \\ Felix Fröhlich, Jun 04 2014
|
|
|
CROSSREFS
|
Cf. A236371, A217131, A191469, A090669, A096305, A217130, A217132, A152213.
Sequence in context: A028378 A325833 A143587 * A039888 A036959 A108031
Adjacent sequences: A096302 A096303 A096304 * A096306 A096307 A096308
|
|
|
KEYWORD
|
nonn,more
|
|
|
AUTHOR
|
Herman H. Rosenfeld (herm3(AT)pacbell.net), Jun 26 2004
|
|
|
EXTENSIONS
|
More terms (probable primes) from Rick L. Shepherd, Jun 29 2004
7 more terms from Jason Earls, Feb 16 2008
a(25)-a(27) from Robert Price, Jan 24 2014
|
|
|
STATUS
|
approved
|
| |
|
|
