OFFSET
1,1
LINKS
K. D. Bajpai, Table of n, a(n) for n = 1..4699
EXAMPLE
31 appears in the sequence because it is prime and 31^6 - 31^5 - 1 = 858874529 is also prime.
101 appears in the sequence because it is prime and 101^6 - 101^5 - 1 = 1051010050099 is also prime.
MAPLE
MATHEMATICA
c = 0; Do[k=Prime[n]; If[PrimeQ[k^6-k^5-1], c++; Print[c, " ", k]], {n, 1, 200000}];
Select[Prime[Range[600]], PrimeQ[#^6-#^5-1]&] (* Harvey P. Dale, Jan 21 2015 *)
PROG
(PARI) s=[]; forprime(p=2, 4000, if(isprime(p^6-p^5-1), s=concat(s, p))); s \\ Colin Barker, Jun 06 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
K. D. Bajpai, Jun 05 2014
STATUS
approved