In my invited talk at IWOP 98, (Leganes, Madrid, Spain), July 1, 1998, on the interaction of combinatorics and analysis, I mentioned the Jewish Spanish school, centered, in Tudela, Spain, that flourished 900 \pm 100 years ago. They excelled both in analysis (i.e. trigonometry) and combinatorics (enumeration). I then mentioned Rabbi Abraham Ibn Ezra's application of combinatorial enumeration to astrology.
Jose L. Fernandez, editor of La Gaceta, the Spanish analog of the Monthly, asked me to write it up, for publication in his journal. This is the outcome.
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