login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

Primes with record large values of the second smallest positive primitive root.
0

%I #2 Mar 31 2012 10:24:40

%S 5,7,11,23,31,191,409,1151,2161,2689,3361,4729,9601,14281,23209,31249,

%T 33049,55441,71761,110881,2116921,3384481,5109721,222855361,288940681,

%U 567719161,831143041,899978641

%N Primes with record large values of the second smallest positive primitive root.

%C Sequence begins at the first prime with at least 2 primitive roots, namely 5.

%e The smallest two positive primitive roots of a(26)=567719161 are 43 and 172. No integer less than 567719161 has a second root greater than or equal to 172.

%Y Cf. A002230.

%K nonn

%O 1,1

%A _Ken Takusagawa_, Nov 27 2006