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%I #10 Sep 22 2014 11:37:18
%S 4189,12193,641941,8778073,26822599,11488195489
%N Composite numbers of the form A242490(n) - 1.
%C a(7) (if it exists) = A242490(k) - 1, k >= 5 * 10^7. - _Hiroaki Yamanouchi_, Sep 22 2014
%e a(1) = A242490(16) - 1 = 4189 = 59 * 71;
%e a(2) = A242490(21) - 1 = 12193 = 89 * 137;
%e a(3) = A242490(125) - 1 = 641941 = 727 * 883;
%e a(4) = A242490(417) - 1 = 8778073 = 2927 * 2999;
%e a(5) = A242490(675) - 1 = 26822599 = 5081 * 5279;
%e a(6) = A242490(10171) - 1 = 11488195489 = 107183 * 107183.
%Y Cf. A242489, A242490, A242716.
%K nonn,more
%O 1,1
%A _Vladimir Shevelev_ and _Peter J. C. Moses_, May 22 2014
%E a(6) from _Hiroaki Yamanouchi_, Sep 22 2014
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