

A112769


Numbers with more than one prime factor and, in the ordered factorization, at least one exponent is less than the previous exponent when read from left to right.


12



12, 20, 24, 28, 40, 44, 45, 48, 52, 56, 60, 63, 68, 72, 76, 80, 84, 88, 90, 92, 96, 99, 104, 112, 116, 117, 120, 124, 126, 132, 135, 136, 140, 144, 148, 152, 153, 156, 160, 164, 168, 171, 172, 175, 176, 180, 184, 188, 189, 192, 198, 200, 204, 207, 208, 212, 220
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OFFSET

1,1


COMMENTS

It appears that this sequence lists the integers x such that A085079(n) > n.  Michel Marcus, Jul 30 2015


LINKS



EXAMPLE

90 = 2^1 * 3^2 * 5^1 and 2 > 1, so 90 is in sequence.


MATHEMATICA

mopfQ[n_]:=Module[{e=FactorInteger[n][[All, 2]]}, Length[e]>1&&Min[ Differences[ e]]<0]; Select[Range[300], mopfQ] (* Harvey P. Dale, May 30 2018 *)


PROG

(PARI) isok(n) = {f = factor(n)[, 2]; if (#f > 1, for (k=2, #f, if (f[k] < f[k1], return (1)); ); ); return (0); } \\ Michel Marcus, Jul 30 2015


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



