Ultrafilters and Abelian Groups
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چکیده
منابع مشابه
Every strongly summable ultrafilter on ⊕ Z 2 is sparse
We investigate the possibility of the existence of nonsparse strongly summable ultrafilters on certain abelian groups. In particular, we show that every strongly summable ultrafilter on the countably infinite Boolean group is sparse. This answers a question of Hindman, Steprāns and Strauss.
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