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%I A171665 #7 Sep 30 2016 11:51:21
%S A171665 44,75,98,104,116,135,147,171,189,230,231,242,243,244,285,296,332,344,
%T A171665 374,375,387,429,434,507,548,603,604,609,645,663,664,724,735,741,776,
%U A171665 782,805,819,844,874,902,903,908,931,963,969,986,1001,1015,1022,1029
%N A171665 Numbers n such that n and n+1 have same number of divisors, and that number of divisors is larger than 4.
%H A171665 Harvey P. Dale, <a href="/A171665/b171665.txt">Table of n, a(n) for n = 1..2000</a>
%t A171665 f[n_]:=Length[Divisors[n]]; lst={};Do[If[f[n]==f[n+1]&&f[n]>4,AppendTo[lst,n]],{n,7!}];lst
%t A171665 Position[Partition[DivisorSigma[0,Range[1100]],2,1],_?(#[[1]] == #[[2]]> 4&),{1},Heads->False]//Flatten (* _Harvey P. Dale_, Sep 30 2016 *)
%Y A171665 Cf. A005237
%K A171665 nonn
%O A171665 1,1
%A A171665 _Vladimir Joseph Stephan Orlovsky_, Dec 14 2009

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