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A110092
Smallest prime ending (through <*2+1> or <*2-1> separately) a complete Cunningham chain (of the first or the second kind) of length n.
0
17, 59, 73, 4079, 47, 2879, 1065601
OFFSET
1,1
COMMENTS
The word "complete" indicates each chain is exactly n primes long for the operator in function (i.e. the chain cannot be a subchain of another one); and the first and/or last term may not be involved in a chain of the other kind (i.e. the chain may not be connected to another one).
LINKS
Chris Caldwell's Prime Glossary, Cunningham chains.
EXAMPLE
a(1)=17 because 2, 3, 5, 7, 11 and 13 are part of longer chains whatever the operator; 17 is the first completely isolated prime.
a(2)=59 because it ends the first two primes chain not connected to another one: 29->59.
KEYWORD
easy,nonn
AUTHOR
Alexandre Wajnberg, Sep 04 2005
EXTENSIONS
Terms computed by Gilles Sadowski.
STATUS
approved