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A158014
Primes p such that (p-1)/8 is also prime.
1
17, 41, 89, 137, 233, 569, 809, 857, 1049, 1097, 1193, 1433, 1913, 2153, 2777, 3209, 3449, 3593, 3833, 3929, 4073, 4457, 4793, 4937, 5273, 5417, 6089, 6473, 6569, 6857, 7433, 7529, 7577, 7817, 9209, 9497, 9833
OFFSET
1,1
LINKS
FORMULA
a(n)=8*A023228(n)+1. - R. J. Mathar, Mar 15 2009
a(n) >> n log^2 n. - Charles R Greathouse IV, Oct 21 2021
MATHEMATICA
Flatten[Table[If[PrimeQ[n] && PrimeQ[(n - 1)/8], n, {}], {n, 1, 10000}]]
Select[Prime[Range[1500]], PrimeQ[(# - 1) / 8]&] (* Vincenzo Librandi, Apr 14 2013 *)
PROG
(PARI) list(lim)=my(v=List()); forprime(p=2, (lim-1)\8, if(isprime(8*p+1), listput(v, 8*p+1))); Vec(v) \\ Charles R Greathouse IV, Oct 20 2021
CROSSREFS
Cf. A005385 for (p-1)/2, A090866 for (p-1)/4, A051644 for (p-1)/6, A055781 for (p-1)/10.
Sequence in context: A299797 A087877 A107181 * A139879 A281792 A293394
KEYWORD
nonn,easy
AUTHOR
Roger L. Bagula, Mar 11 2009
EXTENSIONS
Edited by the Associate Editors of the OEIS, Apr 22 2009
STATUS
approved