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Primes p such that p^3 + p - 1 is prime.
1

%I #13 Mar 01 2020 06:48:47

%S 3,7,43,73,103,109,127,139,151,199,223,241,283,313,367,379,421,541,

%T 631,661,733,739,751,769,829,991,1117,1129,1201,1231,1249,1297,1303,

%U 1429,1471,1663,1669,1693,1699,1741,1789,1867,1933

%N Primes p such that p^3 + p - 1 is prime.

%C Primes in the sequence A236475.

%H Daniel Starodubtsev, <a href="/A236476/b236476.txt">Table of n, a(n) for n = 1..10000</a>

%e 241 is prime and 241^3 + 241 - 1 = 13997761 is prime.

%o (Python)

%o import sympy

%o from sympy import isprime

%o {print(n) for n in range(10**4) if isprime(n) and isprime(n**3+n-1)}

%o (PARI)

%o s=[]; forprime(p=2, 2000, if(isprime(p^3+p-1), s=concat(s, p))); s \\ _Colin Barker_, Jan 27 2014

%Y Cf. A236475.

%K nonn

%O 1,1

%A _Derek Orr_, Jan 26 2014