cp's OEIS Frontend

A152470 Largest of three consecutive primes whose sum is a prime.

%I A152470 #31 Sep 12 2014 15:48:55
%S A152470 11,13,17,23,29,31,37,41,47,61,71,73,79,89,97,107,127,151,157,167,173,
%T A152470 211,227,239,281,293,307,311,317,349,353,359,389,401,419,421,439,461,
%U A152470 463,479,487,503,509,523,563,631,647,661,673,677,719,733,757,761,769
%N A152470 Largest of three consecutive primes whose sum is a prime.
%H A152470 Pierre CAMI, <a href="/A152470/b152470.txt">Table of n, a(n) for n = 1..10000</a>
%e A152470 3+5+7 = 15 is composite.
%e A152470 5+7+11 = 23 is prime and (5, 7, 11) are consecutive primes so a(1) = 11.
%p A152470 Primes:= select(isprime,[2,(2*i+1 $ i=1..10000)]):
%p A152470 Primes[select(t -> isprime(Primes[t-2]+Primes[t-1]+Primes[t]),[$3..nops(Primes)])];
%p A152470 # _Robert Israel_, Aug 29 2014
%t A152470 lst={};Do[p0=Prime[n];p1=Prime[n+1];p2=Prime[n+2];If[PrimeQ[p0+p1+p2],AppendTo[lst,p2]],{n,6!}];lst
%o A152470 (PFGW & SCRIPT)
%o A152470 SCRIPT
%o A152470 DIM n,0
%o A152470 OPENFILEOUT myf,a(n).txt
%o A152470 LABEL loop1
%o A152470 SET n,n+1
%o A152470 PRP p(n)+p(n+1)+p(n+2)
%o A152470 IF ISPRP then GOTO a
%o A152470 GOTO loop1
%o A152470 LABEL a
%o A152470 WRITE myf,t
%o A152470 GOTO loop1
%o A152470 # _Pierre CAMI_, Aug 30 2014
%o A152470 (PARI) s=[]; for(n=1, 1000, if(isprime(prime(n)+prime(n+1)+prime(n+2)), s=concat(s, prime(n+2)))); s \\ _Colin Barker_, Aug 25 2014
%Y A152470 Cf. A073681, A072225, A152468, A152469.
%K A152470 nonn
%O A152470 1,1
%A A152470 _Vladimir Joseph Stephan Orlovsky_, Dec 05 2008