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%I #28 Oct 10 2018 09:23:39
%S 5,17,41,2137,11455307,1178314103
%N a(n) is the first prime p that starts a run of length n of multiples of itself in alternate terms of A254077.
%C a(n) is the first prime p occurring at position m in A254077, satisfying the condition that A254077(m + 2i) = p*(i+2) for all i from 1 through n. Also, A254077(m-2) = p*2.
%C John P. Linderman calculated and confirmed a(6).
%H John P. Linderman, <a href="/A254077/a254077_5.pdf">Notes on computation of first 5 billion terms</a>
%H John Mason, <a href="/A254077/a254077.pdf">Some observations related to A254077</a>
%e a(1)=5 because A254077(10)=5 and A254077(12)=15;
%e a(2)=17 because A254077(33)=17 and A254077(35)=51 and A254077(37)=68.
%Y Cf. A254077.
%K nonn,more
%O 1,1
%A _John Mason_, Sep 05 2018