Abstract.
We show that \({\frak g}<{\frak g}_f\) is consistent, where \({\frak g}\) is the groupwise density number and \({\frak g}_f\) is the groupwise density number for ideals. This answers a question of Heike Mildenberger.
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Partially supported by Grant-in-Aid for Scientific Research (C) 17540116, Japan Society for the Promotion of Science.
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Brendle, J. Distinguishing groupwise density numbers. Mh Math 152, 207–215 (2007). https://doi.org/10.1007/s00605-007-0465-5
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DOI: https://doi.org/10.1007/s00605-007-0465-5