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%I #17 Sep 03 2018 02:53:36
%S 3,4,6,10,13,33,18,42,48,31,58,70,43,82,90,102,110,120,126,140,144,
%T 154,150,182,180,198,200,220,216,228,272,252,280,270,300,306,312,330,
%U 336,340,348,360,390,392,396,400,442,438,468,440,506,480,484,500,486,518,528,540,574,546,570,572,616
%N Numbers in A098550 which appear immediately after a prime.
%C It is conjectured that this is the same as A253048 except for the addition of 3, 13, 31, and 43 (the upper members of the twin primes in A098550).
%C a(n) = A098550(A251239(n)+1). - _Reinhard Zumkeller_, Dec 29 2014
%H Reinhard Zumkeller, <a href="/A253049/b253049.txt">Table of n, a(n) for n = 1..10000</a>
%H David L. Applegate, Hans Havermann, Bob Selcoe, Vladimir Shevelev, N. J. A. Sloane, and Reinhard Zumkeller, The Yellowstone Permutation, 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 f[lst_] := Block[{k = 4}, While[GCD[lst[[-2]], k] == 1 || GCD[lst[[-1]], k] > 1 || MemberQ[lst, k], k++]; Append[lst, k]];
%t A098550 = Nest[f, {1, 2, 3}, 1000];
%t sp = SequencePosition[A098550, {_?PrimeQ, _}] [[All, 2]];
%t A098550[[sp]] (* _Jean-François Alcover_, Sep 03 2018, after _Robert G. Wilson v_ in A098550 *)
%Y Cf. A098550. See A253048 for another version.
%Y Cf. A251239.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Dec 27 2014
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