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A098029
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Primes of the form (prime(n)+ prime(n+3))/2.
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2
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7, 23, 37, 47, 67, 73, 233, 277, 353, 479, 613, 631, 647, 809, 1097, 1283, 1297, 1433, 1453, 1471, 1493, 1607, 1613, 1663, 1709, 1721, 1783, 1867, 1889, 1901, 1931, 1993, 2099, 2137, 2161, 2377, 2383, 2411, 2521, 2621, 2683, 2693, 2713, 2797, 2879, 3049
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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prime(2)=3, prime(2+3)=11. (3+11)/2 = 7
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MATHEMATICA
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Select[(#[[1]]+#[[4]])/2&/@Partition[Prime[Range[500]], 4, 1], PrimeQ] (* Harvey P. Dale, Nov 30 2017 *)
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PROG
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(PARI) f(n, m) = for(x=1, n, y=prime(x)+prime(x+m); if(y%2==0 & isprime(y\2), print1(y\2", ")))
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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