Resumen de Recursion formulae of 1l?+?2l?+?···?+?nland their combinatoric meaning in terms of the tree diagrams

Yukio Kobayashi

• This article derives the recursion formulae of and demonstrates through tree diagrams how the formulae for the cases of l?=?1,?2,?3 are closely related. Visual thinking by diagrams is pedagogically significant for observing patterns hidden in the formulae for .