A068015 - OEIS

%I #15 May 11 2015 05:38:29

%S 21,14,10,6,14,12,4,6,8,16,14,4,26,6,4,6,38,12,10,18,6,6,14,16,14,10,

%T 14,6,16,6,8,6,6,4,6,8,4,8,30,4,6,8,10,12,8,4,8,4,6,32,6,10,6,14,10,6,

%U 14,6,18,16,6,20,4,6,8,10,8,10

%N Gaps between non-twin primes.

%C a(n) >= 4. - _Zak Seidov_, May 11 2015

%H Harvey P. Dale, <a href="/A068015/b068015.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A007510(n+1) - A007510(n). - _Zak Seidov_, May 11 2015

%e The first primes that are not 2 less than or 2 greater than another prime are 2, 23, 37,... (A007510). The second gap is 37-23=14, so a(2)=14.

%t ntpg[n_]:=Module[{prn=Prime[Range[n]],tp},tp=Union[Flatten[Select[ Partition[prn,2,1], Last[#]- First[#] ==2&]]];Differences[Complement[ prn,tp]]]; ntpg[200] (* _Harvey P. Dale_, Apr 09 2012 *)

%Y Cf. A007510.

%K nonn

%O 1,1

%A _Neil Fernandez_, Mar 22 2002