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%I #9 May 21 2017 18:29:37
%S 37,53,89,97,113,121,157,163,173,211,223,233,251,263,277,289,293,307,
%T 317,331,337,343,353,367,373,379,383,389,397,401,409,439,443,449,457,
%U 467,479,487,491,499,503,529,541,547,557,563,577,587
%N Numbers n with omega(n) < omega of 3 nearest larger and 3 nearest smaller neighbors.
%H G. C. Greubel, <a href="/A101940/b101940.txt">Table of n, a(n) for n = 1..10000</a>
%e 37 is in the sequence because it has one unique prime factor (itself), whereas 34, 35, 36, 38, 39 and 40 each have more.
%t For[i=1, i<1000, If[And[Length[FactorInteger[i-3]] > Length[FactorInteger[i]], 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]],Length[FactorInteger[i+3]]> Length[FactorInteger[i]]], Print[i]];i++ ]
%t Select[Range[6500], PrimeNu[#] < Min[PrimeNu[# - 1], PrimeNu[# - 2], PrimeNu[# - 3], PrimeNu[# + 1], PrimeNu[# + 2], PrimeNu[# + 3]] &] (* _G. C. Greubel_, May 21 2017 *)
%Y Cf. A001221, A101934, A101938.
%K easy,nonn
%O 1,1
%A _Neil Fernandez_, Dec 21 2004
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