This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A079364 #27 May 10 2025 14:26:07
%S A079364 9,15,21,25,26,27,33,34,35,39,45,49,50,51,55,56,57,63,64,65,69,75,76,
%T A079364 77,81,85,86,87,91,92,93,94,95,99,105,111,115,116,117,118,119,120,121,
%U A079364 122,123,124,125,129,133,134,135,141,142,143,144,145,146,147,153,154,155
%N A079364 Composite numbers having two composite neighbors.
%C A079364 In other words, composite numbers that are not nearest-neighbors of primes. - _Omar E. Pol_, Jan 02 2009
%C A079364 Complement of A210940. - _Omar E. Pol_, Apr 18 2012
%H A079364 Reinhard Zumkeller, <a href="/A079364/b079364.txt">Table of n, a(n) for n = 1..10000</a>
%t A079364 Select[Range[6! ],!PrimeQ[ # ]&&!PrimeQ[ #-1]&&!PrimeQ[ #+1]&] (* _Vladimir Joseph Stephan Orlovsky_, Apr 26 2010 *)
%t A079364 With[{r=Complement[Range[160],Prime[Range[PrimePi[160]]]]}, Transpose[ Select[ Partition[r,3,1], Differences[#]=={1,1}&]][[2]]] (* _Harvey P. Dale_, Feb 05 2012 *)
%t A079364 Mean/@SequencePosition[Table[If[CompositeQ[n],1,0],{n,200}],{1,1,1}] (* _Harvey P. Dale_, May 10 2025 *)
%o A079364 (Haskell)
%o A079364 a079364 n = a079364_list !! (n-1)
%o A079364 a079364_list = filter
%o A079364 (\x -> a010051' (x - 1) == 0 && a010051' (x + 1) == 0) a002808_list
%o A079364 -- _Reinhard Zumkeller_, Jan 10 2013
%Y A079364 Cf. A000040, A002808, A014574, A045718.
%Y A079364 Cf. A010051, A221309 (subsequence).
%K A079364 nonn
%O A079364 1,1
%A A079364 _Reinhard Zumkeller_, Feb 15 2003