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A111166 Let p(n) denote the n-th prime; p(n) is in the sequence iff p(n)/(p(n+1)-p(n)) is a record. +0
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2, 5, 11, 17, 29, 41, 59, 71, 101, 107, 137, 149, 179, 191, 197, 227, 239, 269, 281, 311, 347, 419, 431, 461, 521, 569, 599, 617, 641, 659, 809, 821, 827, 857, 881, 1019, 1031, 1049, 1061, 1091, 1151, 1229, 1277, 1289, 1301, 1319, 1427, 1451, 1481, 1487, 1607 (list; graph; listen)
OFFSET

0,1

COMMENT

Conjecture: Except for first term, the sequence coincides with A001359. This is true for all primes < 2*10^7.

Conjecture: Except for first term, the sequence coincides with A001359. This is true for all primes < 7*10^16. Let n >= 2 be an integer, N +- 1 and M +- 1 two consecutive twin pairs where M>n*N. Finding a counterexample is the same as finding two consecutive primes P1 and P2 with n*N<P1<M and P2-P1 <= n. However, such gaps are unknown even for n=2.

EXAMPLE

a(0)=2 and the record is 2/(3-2)=2; a(1)<>3 because 3/(5-3)=1.5; a(1)=5 because 5/(7-5)=2.5

CROSSREFS

Cf. A001359.

Sequence in context: A023222 A007491 A124850 this_sequence A064337 A076873 A089440

Adjacent sequences: A111163 A111164 A111165 this_sequence A111167 A111168 A111169

KEYWORD

easy,nonn

AUTHOR

Bernardo Boncompagni (redgolpe(AT)redgolpe.com), Oct 21 2005

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Last modified July 25 07:41 EDT 2008. Contains 142293 sequences.


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