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Numbers n such that abs(n - 4^k) is prime for k = 1..10.
1

%I #23 May 26 2018 11:21:01

%S 525,635,3335,22547,132725,242073,590663,598793,795143,963815,1910433,

%T 2506647,5833497,13032533,13336685,22163097,22291055,27730755,

%U 36069767,39412953,41006745,42520623,44594457,47869577,63735185,73770483,76852937,89703543,100998105

%N Numbers n such that abs(n - 4^k) is prime for k = 1..10.

%H Chai Wah Wu, <a href="/A281549/b281549.txt">Table of n, a(n) for n = 1..1000</a>

%e For n = 525, the primes are {521, 509, 461, 269, 499, 3571, 15859, 65011, 261619, 1048051}.

%t AA = Table[PrimeQ[Abs[n - 4^k]], {n, 1, 150000}, {k, 1, 10}];

%t Flatten[Position[AA, {True, True, True, True, True, True, True, True, True, True}]]

%o (PARI) is(n)=for(k=1, 10, if(!isprime(abs(n-4^k)), return(0))); 1

%Y Cf. A281047.

%K nonn

%O 1,1

%A _José de Jesús Camacho Medina_, Jan 23 2017

%E Extended by _Charles R Greathouse IV_, Jan 24 2017

%E a(25)-a(29) from _Chai Wah Wu_, Jan 25 2017