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1. • CommentRowNumber1.
   • CommentAuthorNoam_Zeilberger
   • CommentTimeJun 26th 2015
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   Author: Noam_Zeilberger
   Format: MarkdownItexI created a stub for [[falling factorial]], mainly to record the simple fact I learned yesterday that it counts the number of injections between two finite sets.

   I created a stub for falling factorial, mainly to record the simple fact I learned yesterday that it counts the number of injections between two finite sets.

2. • CommentRowNumber2.
   • CommentAuthorTodd_Trimble
   • CommentTimeJun 26th 2015
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   Author: Todd_Trimble
   Format: MarkdownItexI added some more material (some of which was also at [[binomial theorem]]), mainly about the context of finite difference calculus.

   I added some more material (some of which was also at binomial theorem), mainly about the context of finite difference calculus.

3. • CommentRowNumber3.
   • CommentAuthorNoam_Zeilberger
   • CommentTimeJun 26th 2015
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   Author: Noam_Zeilberger
   Format: MarkdownItexExcellent, thanks! These additional properties you mention seem to advocate the notation $n^{\underline{k}}$ which you used for the falling factorial at [[binomial theorem]] -- would you prefer to use that as the main notation in this article as well?

   Excellent, thanks! These additional properties you mention seem to advocate the notation $n^{\underline{k}}$ which you used for the falling factorial at binomial theorem – would you prefer to use that as the main notation in this article as well?

4. • CommentRowNumber4.
   • CommentAuthorTodd_Trimble
   • CommentTimeJun 26th 2015
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   Author: Todd_Trimble
   Format: MarkdownItexThanks for asking! That is my own preference, yes.

   Thanks for asking! That is my own preference, yes.

5. • CommentRowNumber5.
   • CommentAuthorNoam_Zeilberger
   • CommentTimeJun 26th 2015
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   Author: Noam_Zeilberger
   Format: MarkdownItexDone.

   Done.