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%I #19 Jan 24 2023 09:37:46
%S 6,7,9,12,13,15,17,19,20,22,26,28,30,31,33,34,35,37,42,43,48,49,50,51,
%T 53,56,58,61,62,63,65,67,68,69,70,71,72,75,78,79,84,85,86,87,89,90,91,
%U 92,94,96,97,98,103,104,105,106,107,110,114,115,117,120,123,124
%N Sums of two rational cubes, excluding cubes and twice cubes.
%C Each term can be written as sum of two rational cubes infinitely many times.
%C These are all the integers A>0 such that the rank of the elliptic curve x^3 + y^3 = A is positive (A060838(A)>0). - _Michael Somos_, Feb 29 2020
%D Wacław Sierpiński, Teoria liczb, cz. II, PWN, Warsaw, 1959, pp. 472-473.
%H <a href="/index/Su#ssq">Index entries for sequences related to sums of cubes</a>
%o (PARI) for(n=1, 124, if(ellanalyticrank(ellinit([0, (4*n)^2]))[1]>0, print1(n, ", ")));
%Y Subsequence of A020897, and hence of A159843.
%Y Cf. A020898, A060838.
%K nonn
%O 1,1
%A _Arkadiusz Wesolowski_, Aug 23 2013