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A086519 a(n) is the least prime not already used such that (a(n)+a(n-1))/2 is prime. 6

%I #5 Dec 05 2013 19:56:19

%S 3,7,19,43,31,103,151,67,79,127,199,163,139,223,331,211,271,283,379,

%T 367,307,439,487,607,547,499,643,571,523,619,463,631,691,727,739,883,

%U 823,751,787,859,907,811,1063,919,1123,1051,967,1171,1087,991,1471,1291

%N a(n) is the least prime not already used such that (a(n)+a(n-1))/2 is prime.

%C Second term onwards every prime == 1 (mod 6). Conjecture: every prime of the type 6k+1 is a member.

%C After the first term, every member = 7 (mod 12). Conjecture: every prime of the form 12k+7 is a member. - _David Wasserman_, Mar 11 2005

%Y Cf. A086522.

%K nonn

%O 0,1

%A _Amarnath Murthy_, Jul 30 2003

%E More terms from _David Wasserman_, Mar 11 2005

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