OFFSET
1,1
COMMENTS
For primes p, q, r the sum p^4 + q^4 + r^4 can be prime only if at least one of p, q, r equals 3. This sequence is the special case q = 11, r = 3.
It is conjectured that the sequence is infinite.
There are prime twins (11, 13) and other consecutive primes (7, 11; 1093, 1097) in the sequence.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
p = 3: 3^4 + 11^4 + 3^4 = 14803 = 113*131, so 3 is not in the sequence.
p = 7: 7^4 + 11^4 + 3^4 = 17123 is prime, so 7 is in the sequence.
p = 11: 11^4 + 11^4 + 3^4 = 29363 is prime, so 11 is in the sequence.
p = 13: 13^4 + 11^4 + 3^4 = 43283 is prime, so 13 is in the sequence.
MATHEMATICA
Select[Prime[Range[200]], PrimeQ[#^4+14722]&] (* Harvey P. Dale, Apr 18 2023 *)
PROG
(Magma) [ p: p in PrimesUpTo(1110) | IsPrime(p^4+14722) ]; // Klaus Brockhaus, May 03 2009
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Ulrich Krug (leuchtfeuer37(AT)gmx.de), Apr 30 2009
EXTENSIONS
Edited and extended beyond 461 by Klaus Brockhaus, May 03 2009
STATUS
approved