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%I #13 May 22 2020 12:44:35
%S 6,10,14,15,18,21,22,26,30,33,34,35,36,38,39,42,46,50,51,54,55,57,58,
%T 62,65,66,69,70,74,75,77,78,82,85,86,87,91,93,94,95,98,100,102,105,
%U 106,108,110,111,114,115,118,119,122,123,129,130,133,134,138,141
%N Numbers with more than one prime factor and, in the ordered factorization, the exponent never decreases when read from left to right.
%F If n = prod_{k=1..m} p(k)^e(k), then m > 1 and e(1) <= e(2) <= ... <= e(m).
%t fQ[n_] := Module[{f = Transpose[FactorInteger[n]][[2]]}, Length[f] > 1 && Min[Differences[f]] >= 0]; Select[Range[2, 200], fQ] (* _T. D. Noe_, Nov 04 2013 *)
%t Select[Range[150],PrimeNu[#]>1&&Min[Differences[FactorInteger[#][[All,2]]]]>=0&] (* _Harvey P. Dale_, May 22 2020 *)
%o (PARI) isok(n) = {my(f = factor(n), nbf = #f~); if (nbf < 2, return (0)); lastexp = 0; for (i=1, nbf, if ((newexp = f[i, 2]) < lastexp, return (0)); lastexp = newexp;); return (1);} \\ _Michel Marcus_, Oct 30 2013
%Y Cf. A097318, A097319, A097320.
%K nonn
%O 1,1
%A _Alex Ratushnyak_, Oct 29 2013
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