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%I #41 Jun 12 2024 17:06:21
%S 23,37,47,53,67,79,83,89,93,97,113,117,119,121,123,127,131,143,145,
%T 157,163,167,173,185,187,203,205,207,211,215,217,219,223,233,245,247,
%U 251,257,263,277,287,289,293,297,299,301,303,307,317,321,323,325,327,331
%N Numbers that are neither the sum nor the difference of two primes.
%C The sequence is obtained by interleaving A099019 and A134797. From Goldbach's conjecture, apparently all terms are odd. - _Bob Selcoe_, Mar 10 2015
%C Intersection of A007921 and A014092. - _Michel Marcus_, Mar 16 2015
%H Michel Marcus, <a href="/A110673/b110673.txt">Table of n, a(n) for n = 1..7596</a>
%H Oliver Knill, <a href="https://arxiv.org/abs/1606.05958">Goldbach for Gaussian, Hurwitz, Octavian and Eisenstein primes</a>, arXiv preprint arXiv:1606.05958 [math.NT], 2016.
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Goldbach%27s_conjecture">Goldbach's conjecture</a>
%t Lim=331; nn=PrimePi[Lim+1]; (* Lim is upper limit of sequence; nn is range of primes to consider *)
%t dif=Union[Flatten[Differences/@Subsets[Prime[Range[nn]],{2}]]]; (* differences of two primes *)
%t sum=Union[Join[Flatten[Total/@Subsets[Prime[Range[nn]],{2}]],Table[2*Prime[n], {n, nn}]]];seq2; (* sums of two primes *)
%t Complement[Range[Lim],dif,sum] (* neither sum nor difference *) (* _James C. McMahon_, Jun 10 2024 *)
%Y Cf. A007921 (not the difference), A014092 (not the sum).
%Y Cf. also A099019, A134797.
%K easy,nonn
%O 1,1
%A _Eric Angelini_, Sep 14 2005
%E Corrected and extended by _Joshua Zucker_, May 04 2006
%E Offset corrected by _Arkadiusz Wesolowski_, May 19 2012
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