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A338944
Rearrangement of primes into complete Cunningham chains of the second kind, sorted by first prime in the chain.
3
2, 3, 5, 7, 13, 11, 17, 19, 37, 73, 23, 29, 31, 61, 41, 43, 47, 53, 59, 67, 71, 79, 157, 313, 83, 89, 97, 193, 101, 103, 107, 109, 113, 127, 131, 137, 139, 277, 149, 151, 163, 167, 173, 179, 181, 191, 197, 199, 397, 211, 421, 223, 227, 229, 457, 233, 239, 241
OFFSET
1,1
COMMENTS
Analogous to A075712 but pertaining instead to primes of the form found in A005382.
LINKS
Chris K. Caldwell, Cunningham Chain (PrimePages, Prime Glossary).
Wikipedia, Cunningham chain.
EXAMPLE
Triangle begins:
2, 3, 5;
7, 13;
11;
17;
19, 37, 73;
23;
29;
31, 61;
41;
...
MATHEMATICA
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]
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Michael De Vlieger, Nov 17 2020
STATUS
approved