OFFSET
1,2
COMMENTS
Also numbers k such that (5*10^k + 7)/3 is prime.
a(20) > 10^5. - Robert Price, Nov 15 2014
LINKS
FORMULA
a(n) = A102025(n) + 1.
MATHEMATICA
Do[ If[ PrimeQ[(5*10^n + 7)/3], Print[n]], {n, 0, 10000}]
CROSSREFS
KEYWORD
more,nonn
AUTHOR
Robert G. Wilson v, Dec 16 2004
EXTENSIONS
Addition of a(16) from Kamada data by Robert Price, Dec 12 2010
a(17)-a(18) from Erik Branger May 01 2013 by Ray Chandler, Aug 16 2013
a(19) from Kamada data by Robert Price, Nov 15 2014
a(20)-a(22) from Kamada data by Tyler Busby, Apr 14 2024
STATUS
approved