It is known that, for n ≤3, ‘ought to have’ can truthfully be replaced by ‘has’ (see (4), and (5), Cor. 6·6). In this paper, this conjecture will be proved for n ≥ 5. The only unsolved case then will be in dimension four.
No takes yet. Share an insight, caveat, or question.
John R. Stallings (1962) studied this question.
Synapse has enriched one closely related paper. Consider it for comparative context: