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A301369
Numbers k such that (9^k + 7^k)/16 is prime.
0
3, 107, 197, 2843, 3571, 4451, 31517, 44819
OFFSET
1,1
COMMENTS
All terms are prime.
The corresponding primes are 67, 79401467172644850007356716446663549450843749853576087044440771380676673442288169290888310265443988907, ...
MAPLE
select(n->isprime((9^n+7^n)/16), [seq(n, n=1..10000, 2)]); # Muniru A Asiru, Mar 27 2018
MATHEMATICA
Select[Range[1, 10000], PrimeQ[(9^n+7^n)/16] &]
PROG
(PARI) forprime(n=3, 10000, if(isprime((9^n+7^n)/16), print1(n, ", ")))
(Magma) [n: n in [1..10000] |IsPrime((9^n+7^n)/16)]
CROSSREFS
KEYWORD
nonn,more,hard
AUTHOR
EXTENSIONS
a(7) from Michael S. Branicky, Apr 29 2023
a(8) from Michael S. Branicky, Jun 22 2024
STATUS
approved