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A251544 List of values of A098550(n+2) for those n for which A098550(n) is a prime.

%I A251544 #21 Sep 05 2018 11:43:43
%S A251544 4,9,25,21,33,26,85,95,115,58,93,111,82,129,329,265,177,427,335,213,
%T A251544 365,237,581,267,679,505,309,321,545,565,381,655,411,973,1043,755,785,
%U A251544 1141,835,519,895,1267,1337,579,985,597,633,1115,1135,687,699,1673,723,753
%N A251544 List of values of A098550(n+2) for those n for which A098550(n) is a prime.
%C A251544 For n > 4: third column in A251637. - _Reinhard Zumkeller_, Dec 16 2014
%H A251544 N. J. A. Sloane, <a href="/A251544/b251544.txt">Table of n, a(n) for n = 1..11246</a>
%H A251544 David L. Applegate, Hans Havermann, Bob Selcoe, Vladimir Shevelev, N. J. A. Sloane, and Reinhard Zumkeller, <a href="http://arxiv.org/abs/1501.01669">The Yellowstone Permutation</a>, arXiv preprint arXiv:1501.01669, 2015 and <a href="https://cs.uwaterloo.ca/journals/JIS/VOL18/Sloane/sloane9.html">J. Int. Seq. 18 (2015) 15.6.7</a>.
%t A251544 max = 600;
%t A251544 f[lst_] := Block[{k = 4}, While[GCD[lst[[-2]], k] == 1 || GCD[lst[[-1]], k] > 1 || MemberQ[lst, k], k++]; Append[lst, k]];
%t A251544 A098550 = Nest[f, {1, 2, 3}, max - 3];
%t A251544 sel = Select[Transpose[{Range[max], A098550}], PrimeQ[#[[2]]]&][[All,1]]+2;
%t A251544 A098550[[sel]] (* _Jean-François Alcover_, Sep 05 2018, after _Robert G. Wilson v_ in A098550 *)
%Y A251544 Cf. A098550, A251542 (another version). See A251545 for the sorted values.
%Y A251544 Cf. A251637.
%K A251544 nonn
%O A251544 1,1
%A A251544 _David Applegate_ and _N. J. A. Sloane_, Dec 16 2014