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A063036
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Difference between average of smallest prime greater than n^3 and largest prime less than (n+1)^3 and n-th pronic [=n(n+1)].
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1
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11, 33, 70, 139, 238, 372, 552, 775, 1058, 1410, 1800, 2290, 2851, 3501, 4232, 5067, 6006, 7048, 8213, 9496, 10901, 12450, 14124, 15951, 17928, 20059, 22358, 24822, 27470, 30284, 33296, 36504, 39898, 43514, 47325, 51364, 55597, 60105, 64822
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OFFSET
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2,1
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COMMENTS
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First term is not an integer.
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LINKS
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EXAMPLE
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n=4: a(4) = 70 because the smallest prime greater than 4^3 is 67, the largest prime less than 5^3 is 113, the average of 67 and 113 is 90, and 90 - 4*5 = 70.
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MATHEMATICA
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Table[Mean[{NextPrime[n^3], NextPrime[(n+1)^3, -1]}]-n(n+1), {n, 2, 40}] (* Harvey P. Dale, Feb 21 2022 *)
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PROG
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(PARI) j=[]; for(n=2, 60, j=concat(j, ((precprime((n+1)^3)+nextprime(n^3))/2)- (n*(n+1))))); j
(PARI) { for (n=2, 1000, a=(precprime((n + 1)^3) + nextprime(n^3))/2 - n*(n + 1); write("b063036.txt", n, " ", a) ) } \\ Harry J. Smith, Aug 16 2009
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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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