arXiv · 0805.0584
We construct groups in which FV^3(n) != δ^2(n). This construction also leads to groups G_k, k >= 3 for which δ^{k}(n) is not subrecursive.
Robert Young. 2009-08-25. Homological and homotopical higher-order filling functions. https://arxiv.org/abs/0805.0584
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