OFFSET
1,1
COMMENTS
a(1) = 5 is the only term that ends in a 5. It is unknown if any term will end in a 3 or 1.
In the first 100,000 primes, no term ends in a 3 or 1. - Harvey P. Dale, Oct 13 2023
EXAMPLE
5 is prime and 5^6 - 5^5 - 5^4 - 5^3 - 5^2 - 5 - 1 = 11719 is prime. Thus 5 is a member of this sequence.
MATHEMATICA
Select[Prime[Range[1000]], PrimeQ[#^6-Total[#^Range[0, 5]]]&] (* Harvey P. Dale, Oct 13 2023 *)
PROG
(Python)
import sympy
from sympy import isprime
{print(n, end=', ') for n in range(10**4) if isprime(n**6-n**5-n**4-n**3-n**2-n-1) and isprime(n)}
(PARI) for(n=1, 10^4, if(ispseudoprime(n)&&ispseudoprime(n^6-sum(i=0, 5, n^i)), print1(n, ", ")))
CROSSREFS
KEYWORD
nonn
AUTHOR
Derek Orr, Jun 04 2014
STATUS
approved