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Dear all,

I have a problem with the numbering of the axis i am using Miktex 2.8 and Tikz and pgfplot and i dont know how to scale the x axis to be {0,2,4,...,20} and y axis {500,1000,....,3500}
i tried \begin{axis}[xmin=2, xmax=20, ymin=500,ymax=3500,

and i tried also
xtick={2, 4, 6, 8, 10, 12 ...