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A101937 Numbers n with omega(n) > omega of 2 nearest larger and 2 nearest smaller neighbors. 2

%I

%S 6,30,42,60,66,70,78,84,90,102,105,110,114,120,126,150,165,174,186,

%T 190,195,198,204,210,234,246,252,255,270,273,276,290,294,300,315,318,

%U 322,330,336,345,354,357,360,385,390,396,399,402,414,420

%N Numbers n with omega(n) > omega of 2 nearest larger and 2 nearest smaller neighbors.

%C Prime factors counted without multiplicity. - _Harvey P. Dale_, Dec 17 2014

%H Harvey P. Dale, <a href="/A101937/b101937.txt">Table of n, a(n) for n = 1..1000</a>

%e 150 is in the sequence because it has three unique prime factors (2,3 and 5), whereas 148, 149, 151 and 152 each have fewer.

%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 gr3Q[{a_,b_,c_,d_,e_}]:=And@@Thread[c>{a,b,d,e}]; Flatten[Position[ Partition[ PrimeNu[Range[500]],5,1],_?(gr3Q[#]&)]]+2 (* _Harvey P. Dale_, Dec 17 2014 *)

%Y Cf. A001221, A076763.

%K easy,nonn

%O 1,1

%A _Neil Fernandez_, Dec 21 2004

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Last modified January 22 04:27 EST 2020. Contains 331133 sequences. (Running on oeis4.)