The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A201828 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A201828

The smallest A(m) such that the interval (A(m)*n, A(m+1)*n) contains exactly one element of A, where A is the sequence of primes p for which p-2 is not prime.
(history; published version)

#41 by Michel Marcus at Wed Dec 03 00:53:07 EST 2014

STATUS

reviewed

approved

#40 by Wesley Ivan Hurt at Wed Dec 03 00:32:26 EST 2014

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proposed

reviewed

#39 by Jon E. Schoenfield at Wed Dec 03 00:24:45 EST 2014

STATUS

editing

proposed

#38 by Jon E. Schoenfield at Wed Dec 03 00:24:42 EST 2014

EXAMPLE

Let n=2. We have the following intervals of the form (2*p,2*q), where p,q are consecutive primes in A025584:(4,6),(6,22),(22,34),(34,46),(46,58),(58,74),(74,82),..., containg containing 0,2,2,2,2,3,1,... primes from A025584. The interval (74,82) is the first to contain exactly one prime from A025584, so a(2)=74/2=37.

STATUS

approved

editing

#37 by Michel Marcus at Mon Apr 28 00:59:54 EDT 2014

STATUS

proposed

approved

#36 by Jon E. Schoenfield at Sun Apr 27 21:22:59 EDT 2014

STATUS

editing

proposed

#35 by Jon E. Schoenfield at Sun Apr 27 21:22:57 EDT 2014

COMMENTS

Conjecture. : For n>=13, every a(n) is the lesser of a pair of cousin primes p and p+4, cf. A023200. Note that it is only conjectured that there are infinitely many pairs of cousin primes.

AUTHOR

Vladimir Shevelev and _Peter J. C. Moses._, _, Jan 09 2013

STATUS

approved

editing

#34 by Bruno Berselli at Tue Feb 19 04:29:48 EST 2013

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reviewed

approved

#33 by Michael B. Porter at Mon Feb 18 23:32:37 EST 2013

STATUS

proposed

reviewed

Discussion

Tue Feb 19

02:27

Vladimir Shevelev: Thank you, Michael, for PARI and editing.

#32 by Michael B. Porter at Mon Feb 18 23:32:15 EST 2013

STATUS

editing

proposed