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 A334964 Numbers that are the sum of three coprime positive cubes 1
 3, 10, 17, 29, 36, 43, 55, 62, 66, 73, 92, 99, 118, 127, 129, 134, 141, 153, 155, 160, 179, 190, 197, 216, 218, 225, 244, 251, 253, 258, 277, 281, 307, 314, 342, 345, 349, 352, 359, 368, 371, 378, 397, 405, 408, 415, 433, 434, 466, 469, 471, 476, 495, 514, 521, 532, 540, 547, 557, 560, 566, 567 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The greatest common divisor of the three cubes must be 1, but they need not be pairwise coprime. LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE a(3)=17 is in the sequence because 17 = 1^3 + 2^3 + 2^3 with gcd(1,2,2)=1. MAPLE N:= 1000: # for all terms <= N S:= {seq(seq(seq(x^3+y^3+z^3, z=select(t -> igcd(x, y, t)=1, [\$y..floor((N-x^3-y^3)^(1/3))])), y=x..floor(((N-x^3)/2)^(1/3))), x=1..floor((N/3)^(1/3)))}: sort(convert(S, list)); PROG (PARI) list(lim)=my(v=List(), s, g, x3); lim\=1; if(lim<3, return([])); for(x=1, sqrtnint(lim\3, 3), x3=x^3; for(y=x, sqrtnint((lim-x3)\2, 3), s=x3+y^3; g=gcd(x, y); if(g>1, for(z=y, sqrtnint(lim-s, 3), if(gcd(g, z)==1, listput(v, s+z^3))), for(z=y, sqrtnint(lim-s, 3), listput(v, s+z^3))))); Set(v) \\ Charles R Greathouse IV, May 18 2020 CROSSREFS Cf. A202679. Sequence in context: A297665 A309347 A273235 * A309351 A003615 A043293 Adjacent sequences:  A334961 A334962 A334963 * A334965 A334966 A334967 KEYWORD nonn AUTHOR Robert Israel, May 17 2020 STATUS approved

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Last modified November 29 12:24 EST 2021. Contains 349416 sequences. (Running on oeis4.)