A156782 - OEIS

%I #4 Jul 11 2013 13:30:08

%S 19,29,43,73,137,149,157,179,211,379,383,401,409,433,467,557,569,577,

%T 599,677,839,863,883,919,997,1103,1303,1499,1553,1637,1669,1709,1783,

%U 1811,1861,1873,1951,2113,2207,2309,2393,2503,2647,2663,2713,2791,3011

%N Primes : if sums of prime number and 4 consecutive prime numbers on-left-and-on-right are also primes.

%C 7+11+13+17+19=67(prime);19+23+29+31+37=139(prime),... prime(n)+prime(n-1)+prime(n-2)+prime(n-3)+prime(n-4) are primes and prime(n)+prime(n+1)+prime(n+2)+prime(n+3)+prime(n+4) are also primes.

%H Harvey P. Dale, <a href="/A156782/b156782.txt">Table of n, a(n) for n = 1..1000</a>

%t lst={};Do[p0=Prime[n+0];p1=Prime[n+1];p2=Prime[n+2];p3=Prime[n+3];p4=Prime[n+4];p5=Prime[n+5];p6=Prime[n+6];p7=Prime[n+7];p8=Prime[n+8];If[PrimeQ[p0+p1+p2+p3+p4]&&PrimeQ[p4+p5+p6+p7+p8],AppendTo[lst,p4]],{n,7!}];lst

%t Transpose[Select[Partition[Prime[Range[500]],9,1], And@@PrimeQ[{Total[ Take[#,5]],Total[Take[#,-5]]}]&]][[5]] (* _Harvey P. Dale_, Jul 11 2013 *)

%Y Cf. A156781

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Feb 15 2009