This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A079614 Decimal expansion of Bertrand's constant. 1
 1, 2, 5, 1, 6, 4, 7, 5, 9, 7, 7, 9, 0, 4, 6, 3, 0, 1, 7, 5, 9, 4, 4, 3, 2, 0, 5, 3, 6, 2, 3, 3, 4, 6, 9, 6, 9 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS From Bertrand's postulate (i.e., there is always a prime p in the range n < p < 2n) one can show there is a constant b such that floor(2^b), floor(2^2^b), ..., floor(2^2^2...^b), ... are all primes. This result is due to Wright (1951), so Bertrand's constant might be better called Wright's constant, by analogy with Mill's constant A051021. - Jonathan Sondow, Aug 02 2013 REFERENCES S. Finch, Mathematical Constants, Cambridge Univ. Press, 2003; see section 2.13 Mill's constant. LINKS C. K. Caldwell, Prime Curios! 137438953481. Pierre Dusart, Estimates of some functions over primes without R. H., arXiv:1002.0442 [math.NT], 2010. J. Sondow, E. Weisstein, Bertrand's Postulate E. M. Wright, A prime-representing function, Amer. Math. Monthly, 58 (1951), 616-618. FORMULA 1.251647597790463017594432053623346969... EXAMPLE 2^(2^(2^1.251647597790463017594432053623)) is approximately 37.0000000000944728917062132870071 and A051501(3)=37. CROSSREFS Cf. A051021, A051501, A060715. Sequence in context: A008343 A257264 A093952 * A238387 A084245 A174232 Adjacent sequences:  A079611 A079612 A079613 * A079615 A079616 A079617 KEYWORD cons,hard,more,nonn AUTHOR Benoit Cloitre, Jan 29 2003 EXTENSIONS More digits (from the Prime Curios page) added by Frank Ellermann, Sep 19 2011 a(16)-a(37) from Charles R Greathouse IV, Sep 20 2011 Definition clarified by Jonathan Sondow, Aug 02 2013 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.