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Tyler Lawson
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Such an example is given by the pair of fibrations $$ K(\mathbb{Z}/2,1) \to K(\mathbb{Z},2) \to K(\mathbb{Z},2) $$ (coming from the Bockstein exact sequence) and by $$ K(\mathbb{Z}/2,1) \to K(\mathbb{Z}/2,1) \times K(\mathbb{Z},2) \to K(\mathbb{Z},2). $$ (a trivial fibration).

In both cases, the (cohomological!) Leray-Serre spectral sequence is concentrated in even total degree. However, the two spaces have differing $H^2$ with integral coefficients ($\mathbb{Z}$ versus $\mathbb{Z} \times \mathbb{Z}/2$).

Tyler Lawson
  • 52.6k
  • 9
  • 187
  • 251