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A071366 Numbers n such that A046523(n) <> A071364(n) and A071364(n) <> n. 2

%I #9 Jul 07 2015 11:08:41

%S 50,75,98,126,147,198,234,242,245,250,294,306,338,342,350,363,375,378,

%T 414,490,500,507,522,525,550,558,578,588,594,605,650,666,686,702,722,

%U 726,735,738,756,774,825,845,846,847,850,867,882,918,950,954,975,980

%N Numbers n such that A046523(n) <> A071364(n) and A071364(n) <> n.

%C Also A046523(n) <> n, as A046523(n) <= A071364(n) <= n.

%e n=50=2*5*5: A071364(50)=2*3*3=18, A046523(50)=2*2*3=12;

%e n=500=2*2*5*5*5: A071364(500)=2*2*3*3*3=108, A046523(500)=2*2*2*3*3=72.

%t Select[Range[1000], (e = Last /@ FactorInteger[ # ]) != Sort[e, Greater] && Product[Prime[i]^e[[i]], {i, Length[e]}] != # &] (* _Ray Chandler_, Sep 23 2005 *)

%Y Cf. A071365.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, May 21 2002

%E Extended by _Ray Chandler_, Sep 23 2005

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Last modified April 23 14:49 EDT 2024. Contains 371914 sequences. (Running on oeis4.)