# Sh:854

• Blass, A. R., & Shelah, S. (2005). Ultrafilters and partial products of infinite cyclic groups. Comm. Algebra, 33(6), 1997–2007.
• Abstract:
We consider, for infinite cardinals \kappa and \alpha\leq\kappa^+, the group \Pi(\kappa,<\alpha) of sequences of integers, of length \kappa, with non-zero entries in fewer than \alpha positions. Our main result tells when \Pi(\kappa,<\alpha) can be embedded in \Pi(\lambda,<\beta). The proof involves some set-theoretic results, one about familes of finite sets and one about families of ultrafilters.
• Version 2004-10-25_11 (15p) published version (12p)
Bib entry
@article{Sh:854,
author = {Blass, Andreas R. and Shelah, Saharon},
title = {{Ultrafilters and partial products of infinite cyclic groups}},
journal = {Comm. Algebra},
fjournal = {Communications in Algebra},
volume = {33},
number = {6},
year = {2005},
pages = {1997--2007},
issn = {0092-7872},
mrnumber = {2150855},
mrclass = {20K20 (03E05 03E10 20K25)},
doi = {10.1081/AGB-200063355},
note = {\href{https://arxiv.org/abs/math/0504199}{arXiv: math/0504199}},
arxiv_number = {math/0504199}
}