Many excellent designs for a new banner were submitted. We will use the best of them in rotation.
1,1
Not proved, only Fermat and Lucas PRPs. Next term is greater than 12000. Concerning primes of the form n * 10^n + n + 1, only n=42 yields one for all n up to 7700.
Table of n, a(n) for n=1..4.
Sequence in context: A157998 A234823 A234816 * A235071 A235064 A070835
Adjacent sequences: A110282 A110283 A110284 * A110286 A110287 A110288
more,nonn
Jason Earls (zevi_35711(AT)yahoo.com), Sep 07 2005
approved