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A056930
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Average of smallest prime greater than n^2 and largest prime less than (n+1)^2.
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4
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6, 12, 20, 30, 42, 57, 73, 90, 107, 133, 158, 183, 210, 239, 270, 305, 345, 382, 420, 461, 505, 556, 598, 652, 702, 753, 813, 870, 930, 994, 1059, 1122, 1193, 1260, 1332, 1406, 1479, 1560, 1635, 1726, 1812, 1897, 1983, 2070, 2168, 2255, 2354, 2444
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OFFSET
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2,1
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COMMENTS
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a(1)=2.5 which is not an integer
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LINKS
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FORMULA
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EXAMPLE
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a(4)=1 because smallest prime greater than 4^2 is 17, largest prime less than 5^2 is 23 and average of 17 and 23 is 20
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MATHEMATICA
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Table[Mean[{NextPrime[n^2], NextPrime[(n+1)^2, -1]}], {n, 2, 50}] (* Harvey P. Dale, May 10 2019 *)
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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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