Found by a rational-parameter search of the Kubert-Tate family for torsion 7, at t=-8/5. In y^2+(1-c)xy-by=x^3-bx^2 the parameters are defined by c=t*(t-1);b=t^2*(t-1); 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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