Found by a rational-parameter search of the Kubert-Tate family for torsion 8, at t=5/17. In y^2+(1-c)xy-by=x^3-bx^2 the parameters are defined by b=(2*t-1)*(t-1);c=b/t; Converted to the global minimal model; PARI/GP ellrank returned bounds [2,2]. The 2 supplied points and the torsion subgroup are independently certified by the site.
Commentary
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