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A087904
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a(n) = the number of twin primes j*(p(n)#)+-1, for 1<=j<(p(n+1))^2.
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0
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3, 10, 16, 19, 30, 40, 34, 45, 49, 47, 55, 53, 52, 53, 63, 74, 75, 68, 77, 73, 72, 73, 79, 95, 77, 67, 72, 84, 75, 94, 92, 96, 97, 100, 100, 94, 93, 107, 91, 92, 78
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| p(n) is the n-th prime; # denotes primorial (A002110).
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FORMULA
| a(n) seems to grow like 16 log p(n).
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EXAMPLE
| a(2)=10 because for j in {1,2,3,5,7,10,12,17,18,23}, j*(3#)+-1 are primes.
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CROSSREFS
| Cf. A002110.
Sequence in context: A175336 A051420 A092827 * A093516 A063209 A063109
Adjacent sequences: A087901 A087902 A087903 * A087905 A087906 A087907
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KEYWORD
| nonn
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AUTHOR
| Pierre CAMI (colettecami(AT)aol.com), Oct 14 2003
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EXTENSIONS
| Edited by Don Reble (djr(AT)nk.ca), Nov 16 2005
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