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A159686
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Sum of strong primes < 10^n.
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0
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OFFSET
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1,2
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COMMENTS
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The number of strong primes < n ~ sum of strong primes < sqrt(n). For number of strong primes < 10^11 = 2014200162 and the sum of strong primes < 10^5.5 = 1972716560, for an error of 0.0206
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LINKS
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FORMULA
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Given 3 consecutive primes p1,p2,p3, p2 is a strong prime if p2 > (p1+p2)/2.
Or, primes that are greater than the arithmetic mean of their immediate surrounding primes.
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EXAMPLE
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The strong primes < 10^2 are 11, 17, 29, 37, 41, 59, 67, 71, 79, 97. These add up to 508 which is the second term in the sequence.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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