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%I #11 May 13 2013 01:54:20
%S 2,18,30,42,52,54,66,68,70,78,90,98,100,102,110,112,114,126,128,130,
%T 138,150,152,162,172,174,182,190,198,210,222,230,232,234,236,238,240,
%U 242,244,250,258,268,270,282,284,286,290,292,294,306,308
%N Even numbers k such that r(k) < r(k/2), where r(n) is the distance from n to the nearest prime.
%H Charles R Greathouse IV, <a href="/A193598/b193598.txt">Table of n, a(n) for n = 1..10000</a>
%e 18 is in the sequence, since r(18) = 1 < 2 = r(9); 22 is not in the sequence, since r(22) = 1 >= 0 = r(11).
%o (PARI) r(n)=min(nextprime(n)-n,n-precprime(n))
%o forstep(k=2,1e3,2,if(r(k)<r(k/2),print1(k", "))) \\ _Charles R Greathouse IV_, Jul 31 2011
%Y r(n) is A051699.
%K nonn
%O 1,1
%A _Vladimir Shevelev_, Jul 31 2011
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