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Search: id:A087907
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| A087907 |
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Numbers n such that n*359# +-1 are twin primes, where 359#=72-nd primorial (A002110(72)). |
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| 983, 1211, 1345, 2134, 2260, 4981, 8102, 9788, 10074, 10406, 10923, 11254, 11821, 11896, 12122, 14428, 14809, 15568, 15758, 17909, 23197, 24634, 25646, 26236, 26781, 27850, 28648, 30739, 31515, 31671, 37875, 40653, 41621, 43983, 44773
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OFFSET
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1,1
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COMMENT
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For the i-th primorial there are roughly floor(16*log(2*P(i))) solutions j for the Diophantine equation: j*P(i)# -1 and +1 are prime twins with i >= 7
For i=72, P(i)=359, 115 j values, int(16*log(2*359))=105
For i=26, P(i)=101, 67 j values, int(16*log(2*101))=73
For i=38, P(i)=163, 107 j values, int(16*log(2*163))=81
For i=50, P(i)=229, 102 j values, int(16*log(2*229))=98
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EXAMPLE
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134464*359# -1 and +1 are twin primes, 134464 is the 115-th j value and the last of this sequence
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CROSSREFS
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P# = A002110.
Sequence in context: A128483 A056937 A122472 this_sequence A096701 A131640 A163025
Adjacent sequences: A087904 A087905 A087906 this_sequence A087908 A087909 A087910
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KEYWORD
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nonn
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AUTHOR
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Pierre CAMI (colettecami(AT)aol.com), Oct 15 2003
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EXTENSIONS
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Needs to be edited in a similar manner to A087820. - N. J. A. Sloane (njas(AT)research.att.com).
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