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A200511 Numbers n with omega(n)=2 and bigomega(n)>2, where omega=A001221=number of distinct prime factors, bigomega=A001222=prime factors counted with multiplicity. 5
12, 18, 20, 24, 28, 36, 40, 44, 45, 48, 50, 52, 54, 56, 63, 68, 72, 75, 76, 80, 88, 92, 96, 98, 99, 100, 104, 108, 112, 116, 117, 124, 135, 136, 144, 147, 148, 152, 153, 160, 162, 164, 171, 172, 175, 176, 184, 188, 189, 192, 196, 200, 207, 208, 212, 216, 224, 225, 232, 236 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Equivalently, numbers of the form n=p^k*q^m where k,m>0, k+m>2 and p,q prime.

It appears that this is equal to A123711.

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Range[240], PrimeNu[#] == 2 && PrimeOmega[#] > 2 &] (* Jean-Fran├žois Alcover, Jun 29 2013 *)

PROG

(PARI) for(n=1, 999, bigomega(n)>2 & omega(n)==2 & print1(n", "))

CROSSREFS

Cf. A200521, A178212.

Sequence in context: A342973 A126706 A123711 * A317711 A323055 A059404

Adjacent sequences:  A200508 A200509 A200510 * A200512 A200513 A200514

KEYWORD

nonn

AUTHOR

M. F. Hasler, Feb 09 2012

STATUS

approved

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Last modified May 15 02:21 EDT 2021. Contains 343909 sequences. (Running on oeis4.)