login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A038458 Decimal expansion of the solution to 127^x - 113^x = 1. This is the smallest x such that q^x - p^x = 1 for two successive primes p, q. 6
5, 6, 7, 1, 4, 8, 1, 3, 0, 2, 0, 2, 0, 1, 7, 7, 1, 4, 6, 4, 6, 8, 4, 6, 8, 7, 5, 5, 3, 3, 4, 8, 2, 5, 6, 4, 5, 8, 6, 7, 9, 0, 2, 4, 9, 3, 8, 8, 6, 3, 8, 2, 0, 6, 8, 4, 0, 2, 8, 5, 2, 2, 1, 8, 2, 6, 8, 0, 6, 7, 6, 6, 3, 3, 8, 2, 7, 6, 9, 2, 1, 5, 0, 8, 8, 6, 9, 7, 3, 8, 5, 3, 6, 4, 2, 6, 4, 4 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
Generalizes Andrica's conjecture prime(n+1)^(1/2) - prime(n)^(1/2) < 1 to prime(n+1)^c - prime(n)^c < 1 if c is less than this number.
Is this constant rational or irrational? I conjecture it is irrational. - Sukanto Bhattacharya (susant5au(AT)yahoo.com.au), Apr 28 2008
The first five digits are the same as the first five of A030178 = LambertW(1). - John W. Nicholson, Dec 11 2013
Although the description of the sequence defines it as "the smallest x" with a certain property, this is conjectured, not yet proven. Numerical evidence supports the conjecture. - Hal M. Switkay, Jun 02 2021
LINKS
Octavian Cira, Smarandache's conjecture on consecutive primes, International J. Math. Combin. 4 (2014), pp. 69-91.
David Lowry-Duda, A short note on gaps between powers of consecutive primes, arXiv:1709.07847 [math.NT], 2017.
M. L. Perez, Five Smarandache conjectures on primes, Arizona State University, Special Collections.
F. Smarandache, Conjectures which generalize Andrica's conjecture, arXiv:0707.2584 [math.GM], 2007; Octogon 7:1 (1999), pp. 173-176.
Eric Weisstein's World of Mathematics, Andrica's Conjecture
Eric Weisstein's World of Mathematics, Smarandache Constants
EXAMPLE
0.567148130202017714646846875533482564586790249388638206840285221826806766338276...
MATHEMATICA
RealDigits[x/.FindRoot[127^x-113^x==1, {x, 0.5}, WorkingPrecision->150]][[1]] (* Harvey P. Dale, Oct 24 2017 *)
PROG
(PARI) default(realprecision, 20080); x=solve(x=.5, .6, 127^x-113^x-1); d=0; for (n=0, 20000, x=(x-d)*10; d=floor(x); write("b038458.txt", n, " ", d)); \\ Harry J. Smith, Apr 13 2009
CROSSREFS
Sequence in context: A214681 A019978 A030178 * A284361 A267017 A358203
KEYWORD
nonn,cons
AUTHOR
M. I. Petrescu (mipetrescu(AT)yahoo.com)
EXTENSIONS
Title improved, incorrect formula deleted, and other edits by M. F. Hasler, Jan 02 2015
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 19 06:21 EDT 2024. Contains 370953 sequences. (Running on oeis4.)