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A101937 Numbers n with omega(n) > omega of 2 nearest larger and 2 nearest smaller neighbors. 1
6, 30, 42, 60, 66, 70, 78, 84, 90, 102, 105, 110, 114, 120, 126, 150, 165, 174, 186, 190, 195, 198, 204, 210, 234, 246, 252, 255, 270, 273, 276, 290, 294, 300, 315, 318, 322, 330, 336, 345, 354, 357, 360, 385, 390, 396, 399, 402, 414, 420 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

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.

MATHEMATICA

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++ ]

CROSSREFS

Cf. A001221, A076763.

Sequence in context: A130512 A127662 A003062 * A101939 A175907 A114649

Adjacent sequences:  A101934 A101935 A101936 * A101938 A101939 A101940

KEYWORD

easy,nonn

AUTHOR

N. Fernandez (primeness(AT)borve.org), Dec 21 2004

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.