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A304634 Numbers n with prime omicron 2, meaning A304465(n) = 2.

%I A304634 #11 May 17 2018 21:35:18
%S A304634 4,6,9,10,12,14,15,18,20,21,22,24,25,26,28,33,34,35,36,38,39,40,44,45,
%T A304634 46,48,49,50,51,52,54,55,56,57,58,60,62,63,65,68,69,72,74,75,76,77,80,
%U A304634 82,84,85,86,87,88,90,91,92,93,94,95,96,98,99,100,104
%N A304634 Numbers n with prime omicron 2, meaning A304465(n) = 2.
%C A304634 If n > 1 is not a prime number, we have A056239(n) >= Omega(n) >= omega(n) >= A071625(n) >= ... >= omicron(n) > 1 where Omega = A001222, omega = A001221, and omicron = A304465.
%e A304634 This is a list of normalized factorizations (see A112798) of selected entries:
%e A304634     4: {1,1}
%e A304634     6: {1,2}
%e A304634    12: {1,1,2}
%e A304634    24: {1,1,1,2}
%e A304634    36: {1,1,2,2}
%e A304634    48: {1,1,1,1,2}
%e A304634    60: {1,1,2,3}
%e A304634    72: {1,1,1,2,2}
%e A304634    96: {1,1,1,1,1,2}
%e A304634   120: {1,1,1,2,3}
%e A304634   144: {1,1,1,1,2,2}
%e A304634   180: {1,1,2,2,3}
%e A304634   192: {1,1,1,1,1,1,2}
%e A304634   216: {1,1,1,2,2,2}
%e A304634   240: {1,1,1,1,2,3}
%e A304634   288: {1,1,1,1,1,2,2}
%e A304634   384: {1,1,1,1,1,1,1,2}
%e A304634   420: {1,1,2,3,4}
%e A304634   432: {1,1,1,1,2,2,2}
%e A304634   480: {1,1,1,1,1,2,3}
%e A304634   576: {1,1,1,1,1,1,2,2}
%e A304634   768: {1,1,1,1,1,1,1,1,2}
%e A304634   840: {1,1,1,2,3,4}
%e A304634   864: {1,1,1,1,1,2,2,2}
%e A304634   960: {1,1,1,1,1,1,2,3}
%t A304634 Join@@Position[Table[Switch[n,1,0,_?PrimeQ,1,_,NestWhile[Sort[Length/@Split[#]]&,Sort[Last/@FactorInteger[n]],Length[#]>1&]//First],{n,100}],2]
%Y A304634 Cf. A001221, A001222, A001358, A005117, A007774, A007916, A055932, A071625, A112798, A181819, A182850, A182857, A275870, A304464, A304465, A304636, A304647.
%K A304634 nonn
%O A304634 1,1
%A A304634 _Gus Wiseman_, May 15 2018