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A065509
Primes p such that p^4 + p^3 + p^2 + p + 1 is prime.
7
2, 7, 13, 17, 23, 29, 43, 73, 79, 83, 127, 193, 227, 239, 263, 277, 337, 359, 373, 397, 439, 457, 479, 503, 557, 563, 617, 919, 967, 1009, 1129, 1187, 1249, 1297, 1327, 1429, 1493, 1553, 1579, 1657, 1663, 1979, 1987, 2069, 2243, 2383, 2617, 2663, 2789
OFFSET
1,1
COMMENTS
Primes in A049409. - Vincenzo Librandi, Aug 07 2010
The generated prime numbers are in A190527. - Bernard Schott, Dec 20 2012
LINKS
Jon E. Schoenfield, Table of n, a(n) for n = 1..10000 (first 1000 terms from Harry J. Smith).
EXAMPLE
a(4) = 17 because 17 is prime and 17^4 + 17^3 + 17^2 + 17 + 1 = 88741 is prime.
MATHEMATICA
f[n_]:=1+n+n^2+n^3+n^4; lst={}; Do[p=Prime[n]; If[PrimeQ[f[p]], AppendTo[lst, p]], {n, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jul 24 2009 *)
Select[Prime[Range[500]], PrimeQ[Total[#^Range[0, 4]]]&] (* Harvey P. Dale, Apr 08 2017 *)
PROG
(PARI) { n=0; for (m=1, 10^9, p=prime(m); if (isprime(p^4 + p^3 + p^2 + p + 1), write("b065509.txt", n++, " ", p); if (n==1000, return)) ) } \\ Harry J. Smith, Oct 20 2009
(PARI) {A065509_vec(N, p=1)=vector(N, i, until(isprime((p^5-1)\(p-1)), p=nextprime(p+1)); p)} \\ M. F. Hasler, Mar 03 2020
(Magma) [n: n in [0..10000]| IsPrime(n) and IsPrime(n^4+n^3+n^2+n+1)] // Vincenzo Librandi, Aug 07 2010
CROSSREFS
Cf. A053182.
Sequence in context: A250185 A063206 A063099 * A094516 A105883 A191036
KEYWORD
easy,nonn
AUTHOR
Vladeta Jovovic, Nov 26 2001
STATUS
approved