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A116008
n + sigma(n) + phi(n) is a cube.
2
8, 120, 496, 914, 3940, 4055, 4252, 8129, 12092, 13779, 14291, 28394, 29948, 41200, 49469, 55255, 58538, 68459, 104512, 114844, 119303, 135068, 135074, 152177, 162127, 170666, 176705, 190595, 220714, 253888, 270916, 285664
OFFSET
1,1
EXAMPLE
914 + sigma(914) + phi(914) = 14^3.
MATHEMATICA
Select[Range[300000], IntegerQ[Surd[#+DivisorSigma[1, #]+EulerPhi[#], 3]]&] (* Harvey P. Dale, May 02 2019 *)
PROG
(PARI) isok(n) = ispower (n + sigma(n) + eulerphi(n), 3); \\ Michel Marcus, Jan 26 2014
CROSSREFS
Sequence in context: A368911 A228752 A360978 * A086302 A053129 A249641
KEYWORD
nonn
AUTHOR
Giovanni Resta, Feb 13 2006
STATUS
approved