OFFSET
1,2
COMMENTS
Also numbers k such that (11*10^k + 61)/9 is prime.
a(13) > 10^5. - Robert Price, Jan 17 2015
a(15) > 2*10^5. - Tyler Busby, Feb 01 2023
LINKS
FORMULA
a(n) = A102011(n) + 1.
MATHEMATICA
Do[ If[ PrimeQ[(11*10^n + 61)/9], Print[n]], {n, 0, 10000}]
CROSSREFS
KEYWORD
more,nonn
AUTHOR
Robert G. Wilson v, Dec 16 2004
EXTENSIONS
a(11)-a(12) from Erik Branger May 01 2013 by Ray Chandler, Aug 16 2013
a(13)-a(14) from Tyler Busby, Jan 31 2023
STATUS
approved