OFFSET
1,2
COMMENTS
Also numbers k such that (8*10^(k+1) + 1)/9 is prime.
a(15) > 2*10^5. - Robert Price, Nov 01 2014
LINKS
FORMULA
a(n) = A096508(n) - 1. - Robert Price, Nov 01 2014
MATHEMATICA
Do[ If[ PrimeQ[ 80*(10^n - 1)/9 + 9 ], Print[n]], {n, 0, 30000}]
CROSSREFS
KEYWORD
hard,nonn
AUTHOR
Robert G. Wilson v, Aug 09 2000
EXTENSIONS
Intermediate missing terms 9811 (from M. Kamada), 12259, 12340, 13759 added by Serge Batalov, Dec 14 2008
a(12)-a(14) derived from A096508 by Robert Price, Nov 01 2014
STATUS
approved