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%I #10 Aug 12 2015 21:01:10
%S 1,8,27,64,125,343,512,729,1331,2197,3375,4096,4913,6859,9261,12167,
%T 15625,19683,24389,29791,32768,35937,39304,42875,50653,54872,59319,
%U 68921,79507,91125,97336,103823,117649,132651,148877,166375,185193
%N Deficient cubes.
%H Harvey P. Dale, <a href="/A125496/b125496.txt">Table of n, a(n) for n = 1..1000</a>
%p with(numtheory): a:=proc(n) if sigma(n^3)<2*n^3 then n^3 else fi end: seq(a(n),n=1..70); # _Emeric Deutsch_, Jan 10 2007
%p isA005100 := proc(n) if numtheory[sigma](n) < 2*n then RETURN(true) ; else RETURN(false) ; fi ; end : for n from 1 to 100 do if isA005100(n^3) then printf("%d,",n^3) ; fi ; od ; # _R. J. Mathar_, Jan 12 2007
%t Select[Range[60]^3,DivisorSigma[1,#]<2#&] (* _Harvey P. Dale_, Feb 15 2014 *)
%Y Intersection of A005100 (deficient numbers) and A000578 (cubes).
%K nonn
%O 1,2
%A _Tanya Khovanova_, Dec 27 2006
%E More terms from _Emeric Deutsch_, Jan 10 2007
%E More terms from _R. J. Mathar_, Jan 12 2007
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