We will show that under ${M\kern -1.8pt A\kern 0.2pt }_{countable}$ for each $k \in \Bbb N$ there exists a group whose $k$-th power is countably compact but whose $2^k$-th power is not countably compact. In particular, for each $k \in \Bbb N$ there exists $l \in [k,2^k)$ and a group whose $l$-th power is countably compact but the $l+1$-st power is not countably compact.
@article{118868, author = {Artur Hideyuki Tomita}, title = {On finite powers of countably compact groups}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {37}, year = {1996}, pages = {617-626}, zbl = {0881.54022}, mrnumber = {1426926}, language = {en}, url = {http://dml.mathdoc.fr/item/118868} }
Tomita, Artur Hideyuki. On finite powers of countably compact groups. Commentationes Mathematicae Universitatis Carolinae, Tome 37 (1996) pp. 617-626. http://gdmltest.u-ga.fr/item/118868/
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