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Steven Sivek
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S3 x RP2 and RP3 x S2 are both smooth 5-manifolds with fundamental group Z/2 and universal cover S3 x S2, so their homotopy groups are all the same. On the other hand, only the latter is orientable since RP3 is orientable but RP2 isn't, so they have different values on H5 and therefore can't be homotopy equivalent. (I think this example is in Hatcher somewhere.)

Steven Sivek
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