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A155215
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a(n) is the average of the smallest prime greater than n and largest prime smaller than n + prime(n).
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1
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2, 3, 6, 6, 10, 12, 17, 17, 21, 24, 27, 30, 35, 35, 39, 42, 46, 46, 53, 56, 56, 60, 66, 69, 71, 71, 78, 80, 84, 85, 97, 97, 102, 102, 109, 109, 117, 120, 120, 126, 127, 127, 140, 140, 144, 144, 155, 161, 162, 165, 168, 168, 176, 176, 185, 188, 188, 188, 196
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(32)= 97. Smallest prime greater than 32 is 37 and p(32)=131, largest prime smaller than 32+p(32) or 163 is 157. So (37+157)/2 = 97
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MATHEMATICA
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Table[(NextPrime[n]+NextPrime[n+Prime[n], -1])/2, {n, 100}] (* Harvey P. Dale, Apr 17 2013 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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Avik Roy (avik_3.1416(AT)yahoo.co.in), Jan 22 2009
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EXTENSIONS
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STATUS
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approved
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