%I #20 Nov 17 2019 09:33:13

%S 91,121,671,703,1541,1729,1891,2821,3281,3367,3751,5551,7381,8401,

%T 8911,10585,11011,12403,14383,15203,16471,16531,18721,19345,23521,

%U 24661,24727,28009,29341,30857,31621,32791,38503,44287,46999,47197,49051,49141,53131

%N Strong pseudoprimes to base 9.

%H Amiram Eldar, <a href="/A020235/b020235.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..369 from R. J. Mathar)

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/StrongPseudoprime.html">Strong Pseudoprime</a>

%H <a href="/index/Ps#pseudoprimes">Index entries for sequences related to pseudoprimes</a>

%Y Cf. A020138, A020229 (base 3), A020307 (base 81).

%K nonn

%O 1,1

%A _David W. Wilson_