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 A165454 Numbers the squares of which are sums of three distinct positive cubes. 3
 6, 15, 27, 48, 53, 59, 71, 78, 84, 87, 90, 96, 98, 116, 120, 121, 125, 134, 153, 162, 163, 167, 180, 188, 204, 213, 216, 224, 225, 226, 230, 240, 242, 244, 251, 253, 255, 262, 264, 280, 287, 288, 303, 314, 324, 330, 342, 350, 356, 363, 368, 372, 381, 384, 393 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Chai Wah Wu, Table of n, a(n) for n = 1..10000 FORMULA {k >0: k^2 in A024975}. [R. J. Mathar, Oct 06 2009] EXAMPLE 6 is in the sequence because 6^2 = 1^3+2^3+3^3. 15 is in the sequence because 15^2 = 1^3+2^3+6^3. MAPLE N:= 1000: # to get all terms <= N sc:= {seq(seq(seq(a^3 + b^3 + c^3, a = 1 .. min(b-1, floor((N^2 - b^3 - c^3)^(1/3)))), b = 2 .. min(c-1, floor((N^2 - c^3)^(1/3)))), c = 3 .. floor(N^(2/3)))}: select(t -> member(t^2, sc), [\$1..N]); # Robert Israel, Jan 27 2015 MATHEMATICA lst={}; Do[Do[Do[d=Sqrt[a^3+b^3+c^3]; If[d<=834&&IntegerQ[d], AppendTo[lst, d]], {c, b+1, 5!, 1}], {b, a+1, 5!, 1}], {a, 5!}]; Take[Union@lst, 123] Sqrt[# ]&/@Select[Total/@Subsets[Range[50]^3, {3}], IntegerQ[Sqrt[#]]&]// Union (* Harvey P. Dale, Oct 14 2020 *) CROSSREFS Cf. A161992, A024973, A025399 Sequence in context: A255605 A171972 A225285 * A333646 A063525 A335267 Adjacent sequences:  A165451 A165452 A165453 * A165455 A165456 A165457 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Sep 20 2009 EXTENSIONS Comments moved to the examples by R. J. Mathar, Oct 07 2009 Title corrected by Jeppe Stig Nielsen, Jan 26 2015 STATUS approved

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Last modified September 24 20:43 EDT 2021. Contains 347651 sequences. (Running on oeis4.)