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Texified because it was on the front page anyway.
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David White
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S3 x RP2$S^3 \times \mathbb{R}P^2$ and RP3 x S2$\mathbb{R}P^3 \times S^2$ are both smooth 5-manifolds with fundamental group Z/2$\mathbb{Z}/2$ and universal cover S3 x S2$S^3 \times S^2$, so their homotopy groups are all the same. On the other hand, only the latter is orientable since RP3$\mathbb{R}P^3$ is orientable but RP2$\mathbb{R}P^2$ isn't, so they have different values on H5$H^5$ and therefore can't be homotopy equivalent. (I think this example is in Hatcher somewhere.)

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.)

$S^3 \times \mathbb{R}P^2$ and $\mathbb{R}P^3 \times S^2$ are both smooth 5-manifolds with fundamental group $\mathbb{Z}/2$ and universal cover $S^3 \times S^2$, so their homotopy groups are all the same. On the other hand, only the latter is orientable since $\mathbb{R}P^3$ is orientable but $\mathbb{R}P^2$ isn't, so they have different values on $H^5$ and therefore can't be homotopy equivalent. (I think this example is in Hatcher somewhere.)

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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.)