cp's OEIS Frontend

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.

A253971 Prime(n) is included iff prime(n) + n^2 is also prime.

This page as a plain text file.
%I A253971 #9 Sep 08 2022 08:46:11
%S A253971 2,3,7,19,37,43,79,113,151,163,193,229,251,281,317,373,397,433,463,
%T A253971 503,577,757,827,911,953,997,1069,1123,1321,1399,1423,1481,1657,1693,
%U A253971 1747,2029,2143,2267,2311,2473,2503,2551,2593,2687,2753,2791,2917,3313,3323
%N A253971 Prime(n) is included iff prime(n) + n^2 is also prime.
%F A253971 a(n) = prime(A064711(n)). - _Michel Marcus_, Feb 04 2015
%e A253971 7 is in this sequence because 7+16=23.
%e A253971 19 is in this sequence because 19+64=83.
%t A253971 Prime[Select[Range[500], PrimeQ[Prime[#] + #^2] &]]
%o A253971 (Magma) [NthPrime(n): n in [1..500] | IsPrime(NthPrime(n)+n^2)];
%o A253971 (PARI) lista(nn) = forprime (n=2, nn, if (isprime(n+primepi(n)^2), print1(n, ", "))); \\ _Michel Marcus_, Feb 04 2015
%Y A253971 Cf. A064711, A061067.
%K A253971 nonn
%O A253971 1,1
%A A253971 _Vincenzo Librandi_, Feb 04 2015