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A098039 Numbers p such that p = (prime(n)+ prime(n+3))/2 is prime for prime indices n=2, 3, 5... 0

%I

%S 7,23,37,47,73,809,1453,1931,2621,3571,3917,4793,7901,8819,9467,10181,

%T 11657,12421,12659,12781,13229,14449,17383,21739,22079,24151,26501,

%U 28663,30881,32749,33353,34439,38083,38501,42467,42703,43397,48091

%N Numbers p such that p = (prime(n)+ prime(n+3))/2 is prime for prime indices n=2, 3, 5...

%e prime(7)+ prime(10) = 17+29. 46/2 = 23, the second term in the table.

%o (PARI) g(n,m) = forprime(x=1,n,y=(prime(x)+prime(x+m)); if(y%2==0&isprime(y/2),print1(y\2",")))

%K easy,nonn

%O 2,1

%A _Cino Hilliard_, Sep 10 2004

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Last modified September 26 13:17 EDT 2021. Contains 347668 sequences. (Running on oeis4.)