OFFSET
1,2
COMMENTS
Also numbers k such that (55*10^k - 1)/9 is prime.
LINKS
MATHEMATICA
Do[ If[ PrimeQ[ 6*10^n + (10^n-1)/9], Print[n]], {n, 0, 10000}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Aug 11 2000
EXTENSIONS
2779, 3889, 4192, 7537, 7945 from Hugo Pfoertner, Oct 19 2004
23938 from Ray Chandler, Sep 25 2010
32632 and 49169 from Ray Chandler, Feb 08 2012
56453 from Serge Batalov, Mar 12 2009 confirmed as next term by Ray Chandler, Feb 09 2012
61097 from Ray Chandler, Feb 09 2012
90211 from Ray Chandler, Feb 10 2012
STATUS
approved