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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 (list; graph; refs; listen; history; text; internal format)
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

Adjacent sequences:  A281044 A281045 A281046 * A281048 A281049 A281050

KEYWORD

nonn

AUTHOR

José de Jesús Camacho Medina, Jan 13 2017

EXTENSIONS

More terms from Charles R Greathouse IV, Jan 13 2017

STATUS

approved

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Last modified December 4 04:22 EST 2020. Contains 338921 sequences. (Running on oeis4.)