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%I #21 Oct 31 2019 01:25:05
%S 9,161,219,4859,21989,52931,88595
%N Numbers k such that the smoothly undulating palindromic number (98*10^k - 89)/99 is a prime.
%C Prime versus probable prime status and proofs are given in the author's table.
%C No further terms < 100000. - _Ray Chandler_, Aug 17 2011
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/undulat.htm#supp989">SUPP Reference Table - 989</a>
%H <a href="/index/Pri#pri_supp">Index entries for sequences related to smoothly undulating palindromic primes</a>
%e k=9 -> (98*10^9 - 89)/99 = 989898989.
%Y Cf. A062209-A062231, A059758, A032758.
%K nonn,base,more
%O 1,1
%A _Patrick De Geest_ and Hans Rosenthal (Hans.Rosenthal(AT)t-online.de), Jun 15 2001
%E a(6)=52931 from _Ray Chandler_, Nov 11 2010
%E a(7)=88595 from _Ray Chandler_, Jul 23 2011
%E Edited by _Ray Chandler_, Aug 17 2011