/usr/lib/libreoffice/share/extensions/nlpsolver/help/en-US/help.key_ is in libreoffice-nlpsolver 0.9+LibO6.0.3-0ubuntu1.
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1 2 | 23 Solver for Nonlinear Problems;Usage 49 com.sun.star.comp.Calc.NLPSolver%2FUsage.xhp#bm_id0603200910434044_scalc;
25 Solver for Nonlinear Problems;Options 4b com.sun.star.comp.Calc.NLPSolver%2FOptions.xhp#bm_id0503200917110375_scalc;
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