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%I #10 Sep 25 2014 09:58:18
%S 7,19,23,26,31,47,53,67,74,76,83,89,97,109,113,119,124,127,131,134,
%T 139,146,159,167,174,181,183,188,199,207,211,215,219,233,244,246,251,
%U 259,263,274,287,293,303,307,314,323,327,337,339,349,353,359,362,367,379,383,386
%N Numbers n such that P(n) > P(n+2) > P(n+1), where P(n) = largest prime factor of n (A006530).
%D Antal Balog, On the largest prime factor of consecutive integers, Abstracts Amer. Math. Soc., 25 (No. 2, 2002), p. 337, #975-11-76.
%H T. D. Noe, <a href="/A082422/b082422.txt">Table of n, a(n) for n = 1..1000</a>
%H 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 With[{lfs=Table[FactorInteger[n][[-1,1]],{n,400}]},Flatten[ Position[ Partition[ lfs,3,1],_?(#[[1]]>#[[3]]>#[[2]]&),{1},Heads->False]]] (* _Harvey P. Dale_, Sep 25 2014 *)
%Y Cf. A006530, A082417-A082421, A071869, A071870.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Apr 25 2003
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