A137472 - OEIS

%I #11 Feb 06 2019 02:20:32

%S 2,3,29,41,71,191,239,701,2309,2531,4229,5261,6491,6971,8009,10559,

%T 11279,11393,11789,12203,12329,14519,17021,18041,18719,20369,23561,

%U 23633,28499,33329,34499,37409,38453,41051,41843,42359,44159

%N Primes p such that p^3 +- (p+1) are primes.

%H Vincenzo Librandi, <a href="/A137472/b137472.txt">Table of n, a(n) for n = 1..1000</a>

%e 2^3 +- 3 -> ( 5,11) (primes);

%e 3^3 +- 4 -> (23,31) (primes).

%p a:=proc(n): if isprime(ithprime(n)^3+ithprime(n)+1)=true and isprime(ithprime(n)^3-ithprime(n)-1)=true then ithprime(n) else end if end proc: seq(a(n),n= 1..4000); # _Emeric Deutsch_, Apr 29 2008

%t Select[Prime[Range[900]],PrimeQ[ #^3-(#+1)]&&PrimeQ[ #^3+(#+1)]&]

%K nonn,easy

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Apr 21 2008

%E More terms from _Stefan Steinerberger_ and _Emeric Deutsch_, Apr 26 2008