Added December 27, 2018.
Taken from https://en.wikipedia.org/wiki/List_of_nonlinear_partial_differential_equations
Sinh Gordon. Solve for \(u(x,t)\) \[ u_{xt} = \sinh u \]
Mathematica ✗
ClearAll["Global`*"]; pde = D[u[x, t], x, t] == Sinh[u[x, t]]; sol = AbsoluteTiming[TimeConstrained[DSolve[pde, u[x, t], {x, t}], 60*10]];
Failed
Maple ✗
restart; pde := diff(u(x,t),x,t)=sinh(u(x,t)); cpu_time := timelimit(60*10,CodeTools[Usage](assign('sol',pdsolve(pde,u(x,t))),output='realtime'));
sol=()
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