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%I #9 May 16 2017 04:30:44
%S 37,53,64,67,89,97,113,121,131,157,163,173,211,223,233,251,263,277,
%T 289,293,307,317,331,337,343,353,367,373,379,383,389,397,401,409,439,
%U 443,449,457,467,479,487,491,499,503,509,512,529,541,547
%N Numbers n with omega(n) < omega of 2 nearest larger and 2 nearest smaller neighbors.
%H G. C. Greubel, <a href="/A101938/b101938.txt">Table of n, a(n) for n = 1..10000</a>
%e 173 is in the sequence because it has one unique prime factor (itself), whereas
%e 171, 172, 174 and 175 each have more.
%t For[i=2, i<1000, If[And[Length[FactorInteger[i-2]]>Length[FactorInteger[i]], Length[FactorInteger[i-1]]>Length[FactorInteger[i]], Length[FactorInteger[i+1]]>Length[FactorInteger[i]], Length[FactorInteger[i+2]]>Length[FactorInteger[i]]], Print[i]];i++ ]
%t Select[Range[6500], PrimeNu[#] < Min[PrimeNu[# - 1], PrimeNu[# - 2], PrimeNu[# + 1], PrimeNu[# + 2]] &] (* _G. C. Greubel_, May 15 2017 *)
%Y Cf. A001221, A101934.
%K easy,nonn
%O 1,1
%A _Neil Fernandez_, Dec 21 2004
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