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Composite numbers of the form A242489(n) - 3.
2

%I #16 Sep 22 2014 07:46:08

%S 12317,50637287,147111617,5174048597

%N Composite numbers of the form A242489(n) - 3.

%C a(5) (if it exists) = A242489(k) - 3, k >= 5 * 10^7. - _Hiroaki Yamanouchi_, Sep 22 2014

%e a(1) = A242489(25) - 3 = 12317 = 109 * 113;

%e a(2) = A242489(900) - 3 = 50637287 = 7103 * 7129;

%e a(3) = A242489(1436) - 3 = 147111617 = 12097 * 12161;

%e a(4) = A242489(7084) - 3 = 5174048597 = 71789 * 72073.

%Y Cf. A242489, A242490, A242770.

%K nonn,more

%O 1,1

%A _Vladimir Shevelev_ and _Peter J. C. Moses_, May 21 2014

%E a(4) from _Hiroaki Yamanouchi_, Sep 22 2014