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A159687
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Number of strong primes < 10^n.
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0
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0, 10, 73, 574, 4543, 37723, 320991, 2796946, 24758534, 222126290, 201400162
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| The number of strong primes < n ~ sum of strong primes < sqrt(n). The 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
| Cino Hilliard, Sum of Strong Primes
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FORMULA
| 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
| The strong primes < 10^2 are 11,17,29,37,41,59,67,71,79,97. These add up
to 10 which is the second term in the sequence.
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PROG
| (Other) See the link for Gcc programs that count and sum these primes.
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CROSSREFS
| Sequence in context: A200580 A181678 A206817 * A199556 A044197 A044578
Adjacent sequences: A159684 A159685 A159686 * A159688 A159689 A159690
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KEYWORD
| nonn
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AUTHOR
| Cino Hilliard (hillcino368(AT)hotmail.com), Apr 19 2009
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EXTENSIONS
| Edited by N. J. A. Sloane, Apr 20 2009
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