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%I #27 Nov 10 2019 01:33:46
%S 3,5,29,157,323,353,1213,1285,7985,15193,84773,119931,148861
%N Numbers k such that (72*10^(k-1) - 27)/9 is a plateau prime.
%C Prime versus probable prime status and proofs are given in the author's table.
%D C. Caldwell and H. Dubner, "Journal of Recreational Mathematics", Volume 28, No. 1, 1996-97, pp. 1-9.
%H Patrick De Geest, <a href="http://www.worldofnumbers.com/deplat.htm#pdp797">PDP Reference Table - 797</a>.
%H Makoto Kamada, <a href="https://stdkmd.net/nrr/7/79997.htm#prime">Prime numbers of the form 799...997</a>.
%H <a href="/index/Pri#Pri_rep">Index entries for primes involving repunits</a>.
%F a(n) = A056263(n) + 2.
%e k=5 -> (72*10^(5-1) - 27)/9 = 79997.
%Y Cf. A082697-A082720, A056263.
%K nonn,base,more
%O 1,1
%A _Patrick De Geest_, Apr 13 2003
%E a(11)=84773 from _Ray Chandler_, Jan 03 2011
%E a(12)=119931 from _Ray Chandler_, Apr 01 2011
%E a(13)=148861 from _Ray Chandler_, Apr 09 2011
%E Edited by _Ray Chandler_, Nov 04 2014
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