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We report on the observation of $\gamma$-rays above 25\,GeV from the Crabpulsar (PSR B0532+21) using the MAGIC I telescope. Two data sets fromobservations during the winter period 2007/2008 and 2008/2009 are used. Inorder to discuss the spectral shape from 100\,MeV to 100\,GeV, one year ofpublic {\it Fermi} Large Area Telescope ({\it Fermi}-LAT) data are alsoanalyzed to complement the MAGIC data. The extrapolation of the exponentialcutoff spectrum determined with the Fermi-LAT data is inconsistent with MAGICmeasurements, which requires a modification of the standard pulsar emissionmodels. In the energy region between 25 and 100\,GeV, the emission in the P1phase (from -0.06 to 0.04, location of the main pulse) and the P2 phase (from0.32 to 0.43, location of the interpulse) can be described by power laws withspectral indices of $-3.1 \pm 1.0_{stat} \pm 0.3_{syst}$ and $-3.5 \pm0.5_{stat} \pm 0.3_{syst}$, respectively. Assuming an asymmetric Lorentzian forthe pulse shape, the peak positions of the main pulse and the interpulse areestimated to be at phases $-0.009 \pm 0.007$ and $0.393 \pm 0.009$, while thefull widths at half maximum are $0.025 \pm 0.008$ and $0.053 \pm 0.015$,respectively.

Observations of the Crab pulsar between 25 GeV and 100 GeV with the MAGIC I telescope