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%I #7 Aug 14 2017 03:18:03
%S 35,87,95,143,203,215,219,303,395,447,635,699,923,1043,1139,1263,1311,
%T 1347,1403,1643,1763,1839,1887,1895,1943,1983,2015,2103,2183,2219,
%U 2307,2363,2435,2463,2519,2643,2667,2723,2735,3099,3387,3603,3695,3731,3867
%N Numbers n such that n, n-1 and n-2 have the same prime signature.
%H Giovanni Resta, <a href="/A086337/b086337.txt">Table of n, a(n) for n = 1..10000</a>
%t sig[n_] := If[n == 1, {}, Last /@ FactorInteger[n]]; Select[Range[3902], sig[#] == sig[# - 1] == sig[# - 2] &] (* _Giovanni Resta_, Aug 14 2017 *)
%Y Cf. A083793.
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Sep 01 2003