OFFSET
1,1
LINKS
Steven Harvey, Generalized Woodall Search
MATHEMATICA
Select[Range[2000], PrimeQ[# 7^# - 1] &]
PROG
(Magma) [n: n in [0..3000] | IsPrime(n*7^n-1)];
(PARI) is(n)=ispseudoprime(n*7^n-1) \\ Charles R Greathouse IV, May 22 2017
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Vincenzo Librandi, May 09 2014
EXTENSIONS
a(5) - a(7) from Harvey's list (see Links).
STATUS
approved