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%I #10 Jan 29 2024 11:47:27
%S 89,8999,89999999,89999999999999999999,899999999999999999999999999999,
%T 89999999999999999999999999999999999999,
%U 8999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999
%N Primes of the form 9*10^k - 1.
%C Equivalently, primes of the form 8*10^k + 9*R_k, where R_k is the repunit (A002275) of length k.
%H Makoto Kamada, <a href="https://stdkmd.net/nrr/8/89999.htm#prime">Prime numbers of the form 899...999</a>.
%H <a href="/index/Pri#Pri_rep">Index entries for primes involving repunits</a>
%Y Cf. A056725 (corresponding k).
%K nonn
%O 1,1
%A _Rick L. Shepherd_, Apr 17 2004
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