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 A082421 #10 Sep 27 2013 15:38:51
%S A082421 3,5,11,15,17,29,35,39,41,44,49,51,55,59,63,65,69,71,80,87,95,99,101,
%T A082421 104,107,111,116,129,137,143,149,153,155,161,164,179,186,191,195,197,
%U A082421 203,209,224,227,230,237,239,242,249,255,265,267,269,272,279,281,285,291,296,299
%N A082421 Numbers n such that P(n+1) < P(n) < P(n+2), where P(n) = largest prime factor of n (A006530).
%D A082421 Antal Balog, On the largest prime factor of consecutive integers, Abstracts Amer. Math. Soc., 25 (No. 2, 2002), p. 337, #975-11-76.
%H A082421 T. D. Noe, <a href="/A082421/b082421.txt">Table of n, a(n) for n = 1..1000</a>
%H A082421 P. Erdős and C. Pomerance, <a href="http://www.math.dartmouth.edu/~carlp/PDF/paper17.pdf">On the largest prime factors of n and n+1</a>, Aequationes Math. 17 (1978), p. 311-321. [<a href="http://www.renyi.hu/~p_erdos/1978-29.pdf">alternate link</a>]
%t A082421 Flatten[Position[Partition[Table[FactorInteger[n][[-1,1]],{n,400}],3,1],_?(#[[2]]<#[[1]]<#[[3]]&),{1},Heads->False]] (* _Harvey P. Dale_, Sep 27 2013 *)
%Y A082421 Cf. A006530, A082417-A082422, A071869, A071870.
%K A082421 nonn
%O A082421 1,1
%A A082421 _N. J. A. Sloane_, Apr 25 2003