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A214442
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Arithmetic mean of next a(n) > 1 successive odd primes is prime.
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2
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OFFSET
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1,1
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COMMENTS
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Two or more primes in the arithmetic mean.
Corresponding prime arithmetic means: 5, 43, 14639, 369687067, 11370090223, 27055575571, 31756143437
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LINKS
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EXAMPLE
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(3+5+7)/3 is prime, so a(1)=3; next (11+13+...+73+79)/18=43 is prime, so a(2)=18.
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MATHEMATICA
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n = 1; Table[n++; s = Prime[n]; num = 1; While[num == 1 || ! PrimeQ[s/num], n++; num++; s = s + Prime[n]]; num, {3}] (* T. D. Noe, Jul 23 2012 *)
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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