用火柴棒搭三角形是同学们并不陌生的游戏 .动一动手 ,不难知道 ,三根火柴棒只能搭成一个三角形 ,不妨记作 ( 1,1,1) ;四根火柴棒不能搭成三角形 ;五根火柴棒可以搭三角形 ,只能搭成一个三角形 ,即 ( 2 ,2 ,1) ;十根 ,二十根 ,三十根 ,甚至四十根 ,五十根……呢 ?肯定能搭三角 Matching triangles with match sticks is a game that is not unfamiliar to students. It is not difficult to know that three match sticks can only be formed into a triangle, so we can record it as (1,1,1); four match sticks cannot be formed. Triangles; the five matchsticks can take a triangle and can only be a triangle, (2, 2, 1); ten, twenty, thirty, or even forty, fifty... sure? Can take the triangle