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In this paper, we study the growth with respect to dimension of quite general
homotopy invariants Q applied to the CW skeleta of spaces. This leads to upper
estimates analogous to the classical “dimension divided by connectivity” bound for
Lusternik–Schnirelmann category. Our estimates apply, in particular, to the
Clapp–Puppe theory of A–category. We use cat1(X) (which is A–category with A the
collection of 1–dimensional CW complexes), to reinterpret in homotopy-theoretical
terms some recent work of Dranishnikov on the Lusternik–Schnirelmann category of
spaces with fundamental groups of finite cohomological dimension. Our main
result is the inequality cat(X) ≤ dim(Bπ1(X)) + cat1(X), which implies and
strengthens the main theorem of Dranishnikov [Algebr. Geom. Topol. 10 (2010)
917–924].
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