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A098031
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Primes p such that p = (prime(n)+ prime(n+4))/2.
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1
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11, 13, 17, 103, 107, 151, 179, 251, 409, 421, 491, 619, 701, 709, 739, 941, 1009, 1051, 1069, 1459, 1487, 1499, 1571, 1759, 1789, 1873, 2281, 2441, 2659, 2671, 2741, 2749, 2789, 2819, 2861, 3011, 3019, 3331, 3389, 3463, 3931, 4001, 4111, 4177, 4229, 4231
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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(3)=5,prime(3+4)=17. (5+17)/2 = 11.
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MATHEMATICA
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Select[Table[(Prime[n]+Prime[n+4])/2, {n, 800}], PrimeQ] (* Harvey P. Dale, Sep 29 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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