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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A275059 Numbers n such that A000010(n) + n^2 is a prime.

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%I A275059 #13 Sep 08 2022 08:46:17
%S A275059 1,2,3,5,11,13,15,19,31,33,35,41,51,53,59,65,83,89,91,101,103,115,131,
%T A275059 141,149,161,163,181,185,187,191,193,199,217,221,233,241,263,281,287,
%U A275059 295,303,329,331,349,373,401,415,419,431,433,445,449,461,463,469,473,499,517
%N A275059 Numbers n such that A000010(n) + n^2 is a prime.
%C A275059 For n >= 2, a(n) is odd and squarefree. - _Robert Israel_, Jul 29 2016
%H A275059 Robert Israel, <a href="/A275059/b275059.txt">Table of n, a(n) for n = 1..10000</a>
%e A275059 5 is a term because A000010(5) + 5^2 = 29 is a prime number.
%p A275059 select(t -> isprime(numtheory:-phi(t) + t^2), [1,2,seq(n,n=3..1000,2)]); # _Robert Israel_, Jul 29 2016
%t A275059 Select[Range[2000], PrimeQ[#^2 + EulerPhi[#]] &]
%o A275059 (Magma) [n: n in [1..800] | IsPrime(n^2+EulerPhi(n))];
%o A275059 (PARI) isok(n) = isprime(eulerphi(n) + n^2); \\ _Altug Alkan_, Jul 27 2016
%Y A275059 Cf. A000010, A259145.
%K A275059 nonn,easy
%O A275059 1,2
%A A275059 _Vincenzo Librandi_, Jul 27 2016