How to find out the number of methods based on the number of parameters?

Question

Mathematics

There are 5 parameters - parse_mode, disable_web_page_preview, disable_notification, reply_to_message_id, reply_markup
In each method they should be repeated 1 time
Methods:
1) parse_mode
2) parse_mode, disable_web_page_preview
3) disable_web_page_preview
...

Answer 1

Combinatorics: combinations
31