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A281047
Numbers n such that abs(n - 4^k) is prime for k = 1..8.
2
483, 525, 635, 2015, 2043, 3335, 3575, 4275, 10317, 14955, 17855, 22547, 49433, 51695, 52773, 79877, 125807, 132725, 176417, 242073, 314177, 451937, 463517, 590663, 598793, 707817, 795143, 798335, 963815, 994565, 1095465
OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
José Camacho Medina, Cadenas de Numeros Primos (in Spanish).
FORMULA
a(n) >> n log^8 n. - Charles R Greathouse IV, Jan 13 2017
EXAMPLE
For n = 483, the primes are {479, 467, 419, 227, 541, 3613, 15901, 65053}.
MATHEMATICA
Select[Range[11*10^5], AllTrue[Abs[#-4^Range[8]], PrimeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jul 28 2020 *)
PROG
(PARI) is(n)=for(k=1, 8, if(!isprime(abs(n-4^k)), return(0))); 1 \\ Charles R Greathouse IV, Jan 13 2017
CROSSREFS
Sequence in context: A263291 A121734 A260976 * A158330 A288082 A251625
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Charles R Greathouse IV, Jan 13 2017
STATUS
approved