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 A271211 #7 Oct 12 2019 15:30:52
%S A271211 8,9,10,14,15,16,20,21,22,38,39,40,44,45,46,68,69,70,80,81,82,98,99,
%T A271211 100,104,105,106,110,111,112,128,129,130,164,165,166,194,195,196,224,
%U A271211 225,226,230,231,232,278,279,280,308,309,310,314,315,316,350,351,352,380
%N A271211 Composite integers sandwiched between primes p, q with q-p = 4.
%H A271211 Harvey P. Dale, <a href="/A271211/b271211.txt">Table of n, a(n) for n = 1..1000</a>
%H A271211 Laurent Coppey, <a href="http://www.numdam.org/item?id=DIA_2011__65-66__1_0">Décompositions multiplicatives directes des entiers</a>, Diagrammes, 65-66 (2011), p. 1-68, in French, see J4 p. 11.
%e A271211 The composite number 8 is sandwiched between primes 7 and 11, and 11-7=4, so 8 is a member of the sequence.
%t A271211 Range[#[[1]]+1,#[[2]]-1]&/@Select[Partition[Prime[Range[100]],2,1],#[[2]]- #[[1]] == 4&]//Flatten (* _Harvey P. Dale_, Oct 12 2019 *)
%o A271211 (PARI) lista(nn) = {forcomposite(c=4, nn, if ((p=precprime(c)) && ((nextprime(c)-p)==4), print1(c, ", ")););}
%Y A271211 Cf. A014574, A029710, A045881.
%K A271211 nonn
%O A271211 1,1
%A A271211 _Michel Marcus_, Apr 02 2016