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Smallest prime of the form n + (n-1) + (n-2) + ...(n-k), k < n, or 0 if no such prime exists.
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%I #4 Dec 05 2013 19:56:31

%S 0,2,3,7,5,11,7,0,17,19,11,23,13,0,29,31,17,0,19,0,41,43,23,47,0,0,53,

%T 0,29,59,31,0,0,67,0,71,37,0,0,79,41,83,43,0,89,0,47,0,97,0,101,103,

%U 53,107,109,0,113,0,59,0,61,0,0,127,0,131,67,0,137,139,71,0,73,0,149,151,0

%N Smallest prime of the form n + (n-1) + (n-2) + ...(n-k), k < n, or 0 if no such prime exists.

%C Trivially a(n) = 0 if n and 2n-1 both are composite. i.e. (k = 0 or 1.)

%C If a(n) > 0 then a(n) = A034694(n-1). - _David Wasserman_, Jun 07 2005

%K nonn

%O 1,2

%A _Amarnath Murthy_, Sep 17 2003

%E More terms from _David Wasserman_, Jun 07 2005