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%I #16 Jul 19 2016 10:54:43
%S 2,5,11,13,17,29,31,23,29,41,37,41,53,59,61,53,59,73,71,73,83,89,97,
%T 101,97,89,97,109,113,127,131,137,131,127,131,127,137,149,157,163,173,
%U 181,167,157,167,173,181,191,193,197,211,223,229,223,211,223,241,227,223
%N Primes arising as the arithmetic mean of a pair of successive terms of A086517.
%H Reinhard Zumkeller, <a href="/A086518/b086518.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = (A086517(n)+A086517(n+1))/2. - _David Wasserman_, Mar 10 2005
%e 2 = (1+3)/2, 11 = (7+15)/2, etc.
%o (PARI) v=[1]; n=1; while(n<100, s=(n+v[#v])/2; if(type(s)=="t_INT", if(isprime(s)&&!vecsearch(vecsort(v), n), print1(s,", "); v=concat(v, n); n=0)); n++) \\ _Derek Orr_, Jun 16 2015
%o (Haskell)
%o a086518 n = a086518_list !! (n-1)
%o a086518_list = zipWith ((flip div 2 .) . (+))
%o a086517_list $ tail a086517_list
%o -- _Reinhard Zumkeller_, Jun 30 2015
%Y Cf. A086517, A259602, A259603, A259604, A259605.
%K nonn
%O 1,1
%A _Amarnath Murthy_, Jul 30 2003
%E More terms from _David Wasserman_, Mar 10 2005
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