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A062530
Smallest prime p such that there is a gap of 2^n between p and previous prime.
2
3, 5, 11, 97, 1847, 5623, 89753, 3851587, 1872852203, 1999066711903, 22790428875365903, 5333419265419188034369535864127397, 55128448018333565337014555712123010955456071077000028555991473847
OFFSET
0,1
COMMENTS
The next two terms are <= 13615411331526592827872074749865096844383295034548454421 and 768784577114627305753353689789300110953010089817032096740065409732504678169114467301254783622575120297131239844 respectively. - Larry Reeves (larryr(AT)acm.org), Jun 13 2002
LINKS
Thomas R. Nicely, First occurrence prime gaps. [For local copy see A000101]
FORMULA
a(n) = A000230(2^(n-1)) + 2^n = Min{p | p-prevprime(p) = 2^n}. - Amarnath Murthy, Feb 24 2002
a(n) = A151800(A062529(n)). - Amiram Eldar, Nov 04 2024
EXAMPLE
a(2) = 11 because 7 and 11 are consecutive primes with difference 4. - Sascha Kurz, Mar 05 2002
PROG
(PARI) a(n) = {q = 2; p = nextprime(q+1); gap = 2^n; while(p - q != gap, q = p; p = nextprime(p+1)); p; } \\ Michel Marcus, Dec 26 2013
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Labos Elemer, Jun 25 2001
EXTENSIONS
More terms from Sascha Kurz, Mar 05 2002
Further terms from Larry Reeves (larryr(AT)acm.org), Jun 13 2002
Edited by N. J. A. Sloane Aug 31 2009 at the suggestion of R. J. Mathar
a(11)-a(12) calculated from the data at A062529 by Amiram Eldar, Nov 04 2024
STATUS
approved