OFFSET
1,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
MAPLE
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
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
MATHEMATICA
Select[Range[60]^3, DivisorSigma[1, #]<2#&] (* Harvey P. Dale, Feb 15 2014 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Tanya Khovanova, Dec 27 2006
EXTENSIONS
More terms from Emeric Deutsch, Jan 10 2007
More terms from R. J. Mathar, Jan 12 2007
STATUS
approved