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%I #9 Apr 23 2018 08:37:43
%S 2,3,5,7,9,11,13,17,20,23,27,29,31,35,40,43,46,50,52,55,59,63,69,74,
%T 76,78,80,82,90,98,102,105,110,115,118,123,127,131,136,139,144,149,
%U 151,153,159,170,177,179,181,185,188,193,200,205,210,213,216,220,222,227,238,246,248
%N a(n) is the position of (prime(n+1) + prime(n+2))/2 in the ordered nonprimes.
%H Ivan Neretin, <a href="/A024678/b024678.txt">Table of n, a(n) for n = 1..10000</a>
%t (# - PrimePi[#]) & /@ Table[(Prime[n + 1] + Prime[n + 2])/2, {n, 63}] (* _Ivan Neretin_, Apr 22 2018 *)
%K nonn
%O 1,1
%A _Clark Kimberling_