##  [Shelah Rank](/shelah-rank) 

  ##  [Shelah Rank](https://mathlogic.quantumdictionary.io/shelah-rank-0) 

  

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**Mathematics & Logic Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A family of combinatorial/ordinal ranks introduced by Saharon Shelah (commonly under names like 2-rank, D-rank, or more generally Shelah ranks) that measure the combinatorial complexity of formulas and theories; different variants capture different dividing lines in classification theory.