OFFSET
1,3
COMMENTS
p sequence starts 181, 32941, 17361883459, 4822959955971812408731, ...
a(13) corresponds to a 12,272-digit BPSW-probable prime. - Charles R Greathouse IV, Apr 22 2012
PROG
(PARI) p=13; for(i=1, 9, k=1; while(!ispseudoprime(t=(k*p)^2+k*p-1), k++); p=t; print1(k", ")) \\ Charles R Greathouse IV, Apr 20 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Pierre CAMI, Jul 01 2006
EXTENSIONS
a(9)-a(12) from Charles R Greathouse IV, Apr 20 2012
a(13) from Charles R Greathouse IV, Apr 22 2012
STATUS
approved