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A023338
Primes that remain prime through 5 iterations of function f(x) = 3x + 10.
1
233, 709, 11699, 16417, 24481, 31663, 63317, 94999, 172279, 185243, 205081, 228713, 240347, 266681, 285539, 334511, 372059, 395719, 479327, 583501, 734197, 786613, 856627, 863711, 1146091, 1187167, 1188259, 1423067, 1534591, 1562269, 1594301
OFFSET
1,1
COMMENTS
Primes p such that 3*p+10, 9*p+40, 27*p+130, 81*p+400 and 243*p+1210 are also primes. - Vincenzo Librandi, Aug 05 2010
FORMULA
a(n) == 9 (mod 14). - John Cerkan, Oct 11 2016
MATHEMATICA
rp5Q[p_]:=AllTrue[Rest[NestList[3#+10&, p, 5]], PrimeQ]; Select[Prime[ Range[ 150000]], rp5Q] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 17 2020 *)
PROG
(Magma) [n: n in [1..25000000] | IsPrime(n) and IsPrime(3*n+10) and IsPrime(9*n+40) and IsPrime(27*n+130) and IsPrime(81*n+400) and IsPrime(243*n+1210)] // Vincenzo Librandi, Aug 05 2010
(PARI) is(n)=isprime(n) && isprime(3*n+10) && isprime(9*n+40) && isprime(27*n+130) && isprime(81*n+400) && isprime(243*n+1210) \\ Charles R Greathouse IV, Oct 11 2016
CROSSREFS
Subsequence of A023211, A023249, A023280, and A023310.
Sequence in context: A097447 A142783 A142848 * A108820 A230392 A003537
KEYWORD
nonn
EXTENSIONS
Definition clarified by Harvey P. Dale, Mar 17 2020
STATUS
approved