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A066216
Noncube numbers which are sums of cubes of some subset of divisors.
4
36, 72, 252, 288, 378, 520, 576, 584, 738, 756, 792, 828, 855, 954, 972, 1044, 1350, 1440, 1520, 1540, 1764, 1800, 1890, 1944, 1980, 2016, 2070, 2160, 2304, 2352, 2376, 2400, 2484, 2520, 2548, 2556, 2700, 2772, 2808, 2820, 2870, 2880, 3024, 3220, 3240
OFFSET
1,1
LINKS
Jean-François Alcover, Table of n, a(n) for n = 1..1600
EXAMPLE
72 is in the list since 72 = 2^3 + 4^3 and 2 and 4 are divisors of 72
MATHEMATICA
okQ[k_] := AnyTrue[Subsets[Select[Divisors[k]^3, # <= k&]], Total[#]==k&];
Reap[For[k = 1, k <= 100000, k++, If[!IntegerQ[k^(1/3)] && okQ[k], Print[k]; Sow[k]]]][[2, 1]] (* Jean-François Alcover, May 27 2024 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Erich Friedman, Dec 17 2001
STATUS
approved