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A338944 Rearrangement of primes into complete Cunningham chains of the second kind, sorted by first prime in the chain.

%I A338944 #8 Nov 17 2020 21:06:53
%S A338944 2,3,5,7,13,11,17,19,37,73,23,29,31,61,41,43,47,53,59,67,71,79,157,
%T A338944 313,83,89,97,193,101,103,107,109,113,127,131,137,139,277,149,151,163,
%U A338944 167,173,179,181,191,197,199,397,211,421,223,227,229,457,233,239,241
%N A338944 Rearrangement of primes into complete Cunningham chains of the second kind, sorted by first prime in the chain.
%C A338944 Analogous to A075712 but pertaining instead to primes of the form found in A005382.
%H A338944 Michael De Vlieger, <a href="/A338944/b338944.txt">Table of n, a(n) for n = 1..10000</a>
%H A338944 Chris K. Caldwell, <a href="https://primes.utm.edu/glossary/page.php?sort=CunninghamChain">Cunningham Chain</a> (PrimePages, Prime Glossary).
%H A338944 Wikipedia, <a href="https://en.wikipedia.org/wiki/Cunningham_chain">Cunningham chain</a>.
%e A338944 Triangle begins:
%e A338944 2, 3, 5;
%e A338944 7, 13;
%e A338944 11;
%e A338944 17;
%e A338944 19, 37, 73;
%e A338944 23;
%e A338944 29;
%e A338944 31, 61;
%e A338944 41;
%e A338944 ...
%t A338944 Block[{a = {2}, j = 1, k, p}, Do[k = j; If[PrimeQ@ a[[-1]], AppendTo[a, 2 a[[-1]] - 1], While[! FreeQ[a, Set[p, Prime[k]]], k++]; j++; Set[a, Append[a[[1 ;; -2]], p]]], 10^3]; a]
%Y A338944 Cf. A005382, A075712, A338946.
%K A338944 nonn,tabf
%O A338944 1,1
%A A338944 _Michael De Vlieger_, Nov 17 2020