|
| |
|
|
A057469
|
|
Prime numbers k such that (2^k + 3^k)/5 is prime.
|
|
26
|
|
|
|
3, 7, 11, 83, 149, 223, 599, 647, 1373, 8423, 149497, 388897
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
LINKS
|
Table of n, a(n) for n=1..12.
|
|
|
MATHEMATICA
|
Do[ If[ PrimeQ[ n ], If[ PrimeQ[ (3^n + 2^n)/5 ], Print[ n ] ] ], {n, 0, 6270} ]
|
|
|
PROG
|
(PARI) is(n)=isprime(n) && ispseudoprime((2^n + 3^n)/5) \\ Charles R Greathouse IV, Apr 28 2015
(Magma) [p: p in [3..1000] | IsPrime(p) and IsPrime((2^p + 3^p) div 5)]; // Jinyuan Wang, Dec 22 2019
|
|
|
CROSSREFS
|
Cf. A127908 (primes of the form (3^k+2^k)/5).
Sequence in context: A016081 A287301 A105762 * A247229 A082598 A082599
Adjacent sequences: A057466 A057467 A057468 * A057470 A057471 A057472
|
|
|
KEYWORD
|
nonn,more
|
|
|
AUTHOR
|
Robert G. Wilson v, Sep 09 2000
|
|
|
EXTENSIONS
|
More terms from Kamil Duszenko (kdusz(AT)wp.pl), Apr 11 2003
Definition corrected by Alexander Adamchuk, Feb 06 2007
a(11) corresponding to a probable prime with 71328 digits from Jean-Louis Charton, Oct 14 2010
a(12) corresponding to a probable prime with 185551 digits from Jean-Louis Charton, Sep 18 2011
|
|
|
STATUS
|
approved
|
| |
|
|
