%I A005602 M4885
%S A005602 13,3,41,509,2,89,1122659,19099919,85864769,26089808579,
%T A005602 665043081119,554688278429,4090932431513069,95405042230542329
%N A005602 Smallest prime beginning a complete Cunningham chain of length n (of 
               the first kind).
%C A005602 The word "complete" indicates each chain is exactly n primes long (i.e. 
               the chain cannot be a subchain of another one). Except for a(1), 
               each term, by definition, is a Sophie Germain prime (A005384) as 
               is each element except the last in each chain; each element after 
               the first in each chain is a safe prime (A005385), so interior elements 
               are both.
%D A005602 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A005602 G. Loh [ Loeh ], Long chains of nearly doubled primes, Math. Comp., 53 
               (1989), 751-759.
%H A005602 C. Caldwell, <a href="http://primes.utm.edu/glossary/page.php?sort=CunninghamChain">
               The Prime Number Glossary: Cunningham Chains</a>.
%H A005602 W. Roonguthai, <a href="http://ksc9.th.com/warut/cunningham.html">Yves 
               Gallot's Proth.exe and Cunningham Chains</a>
%Y A005602 Cf. (A005384 and A005385), A007700, A023272, A023302, A023330, A057331, 
               A005603.
%Y A005602 Sequence in context: A128154 A107806 A138965 this_sequence A155847 A010219 
               A056139
%Y A005602 Adjacent sequences: A005599 A005600 A005601 this_sequence A005603 A005604 
               A005605
%K A005602 nonn
%O A005602 1,1
%A A005602 N. J. A. Sloane (njas(AT)research.att.com).
%E A005602 a(13) found by Jack Brennen; a(14) found by Paul Jobling (Paul.Jobling(AT)WhiteCross.com) 
               [Oct 23 2000]
%E A005602 Better description from Rick L. Shepherd (rshepherd2(AT)hotmail.com), 
               Jul 07 2004