OFFSET
1,1
COMMENTS
Also numbers k such that (22*10^k - 31)/9 is prime.
a(16) > 10^5. - Robert Price, Apr 11 2015
LINKS
FORMULA
a(n) = A101957(n) + 1.
MATHEMATICA
Do[ If[ PrimeQ[(22*10^n - 31)/9], Print[n]], {n, 0, 10000}]
CROSSREFS
KEYWORD
more,nonn
AUTHOR
Robert G. Wilson v, Dec 17 2004
EXTENSIONS
Addition of a(12) from Kamada data by Robert Price, Dec 13 2010
a(13) from Erik Branger May 01 2013 by Ray Chandler, Aug 16 2013
a(14)-a(15) from Robert Price, Apr 11 2015
STATUS
approved