Documentation
Publicon
Reference
Preferences
Formatting Options
Automatic Numbering Options
Counter Display Options
CounterStyle
• CounterStyle is an option for cells that determines the cell style from which the default values of all options associated with a counter are inherited.
• CounterStyle can be set to any of the cell styles defined in the notebook.
• With the default setting CounterStyle 
Automatic, the counter inherits the option values of the cell style for which the counter is defined.
CounterFunction
• CounterFunction is an option for cells that determines the symbols used to display the value of a counter.
• With the default setting CounterFunction Identity, the value of the counter is displayed as an ordinary decimal number.
• You can also set the counter display to use symbols such as Roman numerals or Greek letters. Other possible formats include: capital Roman numerals, capital Greek letters, lowercase letters, uppercase letters, days of the week, months, and circled numbers. To choose any of these formats, check the corresponding item in the pop-up menu to the right of the option.
• At the level of the cell expression, all these formats are implemented using the CharacterRange function. This allows you to specify any arbitrary set of symbols or strings to use in the counter display. For example,
To display: Use the setting:
abc... CounterFunction (Part[CharacterRange["a", "z"],#]&
Greek letters CounterFunction (Part[CharacterRange["\[Alpha]","\[Omega]"],#]&
Days of the week CounterFunction (Part[CharacterRange[{"Monday", "Tuesday", ...}],#]
