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%I #18 Nov 10 2019 01:33:01
%S 3,9,141,231,427,463,727,1975,7231,45861,47305
%N Numbers k such that (32*10^(k-1) - 23)/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#pdp353">PDP Reference Table - 353</a>.
%H Makoto Kamada, <a href="https://stdkmd.net/nrr/3/35553.htm#prime">Prime numbers of the form 355...553</a>.
%H <a href="/index/Pri#Pri_rep">Index entries for primes involving repunits</a>.
%F a(n) = A056254(n) + 2.
%e k=9 -> (32*10^(9-1) - 23)/9 = 355555553.
%Y Cf. A082697-A082720, A056254.
%K nonn,base,hard,more
%O 1,1
%A _Patrick De Geest_, Apr 13 2003
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 02 2008
%E Edited by _Ray Chandler_, Nov 05 2014
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