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Groups and FieldsHardThe Sylow Theorems

The Sylow Theorems · Hard problem

D44D_{44}, the symmetries of a regular 4444-gon, has order 88=23⋅1188=2^3\cdot11. A Sylow 22-subgroup has order 88, built from the rotations through multiples of 44 steps (there are 44/4=1144/4=11 such rotations) together with the matching reflections. How many Sylow 22-subgroups does D44D_{44} have?