Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #26 Jul 28 2020 19:17:57
%S 483,525,635,2015,2043,3335,3575,4275,10317,14955,17855,22547,49433,
%T 51695,52773,79877,125807,132725,176417,242073,314177,451937,463517,
%U 590663,598793,707817,795143,798335,963815,994565,1095465
%N Numbers n such that abs(n - 4^k) is prime for k = 1..8.
%H Charles R Greathouse IV, <a href="/A281047/b281047.txt">Table of n, a(n) for n = 1..10000</a>
%H José Camacho Medina, <a href="http://matematicofresnillense.blogspot.mx/2016/08/cadenas-de-numeros-primos.html">Cadenas de Numeros Primos</a> (in Spanish).
%F a(n) >> n log^8 n. - _Charles R Greathouse IV_, Jan 13 2017
%e For n = 483, the primes are {479, 467, 419, 227, 541, 3613, 15901, 65053}.
%t Select[Range[11*10^5],AllTrue[Abs[#-4^Range[8]],PrimeQ]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jul 28 2020 *)
%o (PARI) is(n)=for(k=1,8,if(!isprime(abs(n-4^k)), return(0))); 1 \\ _Charles R Greathouse IV_, Jan 13 2017
%K nonn
%O 1,1
%A _José de Jesús Camacho Medina_, Jan 13 2017
%E More terms from _Charles R Greathouse IV_, Jan 13 2017