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%I #18 Nov 30 2017 16:56:51
%S 7,23,37,47,67,73,233,277,353,479,613,631,647,809,1097,1283,1297,1433,
%T 1453,1471,1493,1607,1613,1663,1709,1721,1783,1867,1889,1901,1931,
%U 1993,2099,2137,2161,2377,2383,2411,2521,2621,2683,2693,2713,2797,2879,3049
%N Primes of the form (prime(n)+ prime(n+3))/2.
%C The union of {7}, A119381 and A117876. - _Irina Gerasimova_, Jul 11 2013
%H Harvey P. Dale, <a href="/A098029/b098029.txt">Table of n, a(n) for n = 1..1000</a>
%e prime(2)=3, prime(2+3)=11. (3+11)/2 = 7
%t Select[(#[[1]]+#[[4]])/2&/@Partition[Prime[Range[500]],4,1],PrimeQ] (* _Harvey P. Dale_, Nov 30 2017 *)
%o (PARI) f(n,m) = for(x=1,n,y=prime(x)+prime(x+m);if(y%2==0 & isprime(y\2), print1(y\2",")))
%K easy,nonn
%O 1,1
%A _Cino Hilliard_, Sep 10 2004.
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