plotting - Inaccurate plot

Could someone please tell me how I can increase the accuracy of this plot, please? Or is there some other reason the lines are breaking up?

m = 60;
ContourPlot[{Re[Table[BernoulliB[n, (x + I y)], {n, m, m}]], 
Im[Table[BernoulliB[n, (x + I y)], {n, m, m}]]}, {x, -5, 6}, {y, -10, 10}, 

AspectRatio -> Automatic]

enter image description here

Answer

As you already know from the comments, increasing MaxRecursion or PlotPoints helps, where I would prefer the first one.

In the case of your function, you can gain some speed by compiling the expression. Then, you can set MaxRecursion to a higher value and the plot is still reasonable fast. The code below runs in about 3 seconds here

m = 60;
With[{cf = (Compile[{{x, _Real, 0}, {y, _Real, 0}},
        #, RuntimeOptions -> "Speed", CompilationTarget -> "C"] & /@


           Flatten[{Re[Table[BernoulliB[n, (x + I y)], {n, m, m}]], 
        Im[Table[BernoulliB[n, (x + I y)], {n, m, m}]]}])},
  (#1[args__?NumericQ] := #2[args]) & @@@ Transpose[{{f1, f2}, cf}]
  ];

ContourPlot[{f1[x, y], f2[x, y]}, {x, -5, 6}, {y, -10, 10}, 
 AspectRatio -> Automatic, MaxRecursion -> 3]

Mathematica graphics

Comments

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