# Definition of ordered triple [duplicate]

Why this is not a correct definition for ordered triple? (I know that the correct definition is Kuratowski's definition)

for any $$a,b,c$$ : $$ = \{ \{a\}, \{a, b\}, \{a, b, c\} \}$$

At the first time I saw the definition of ordered pair I thougt this is correct but according to kuratowski's definition it is not and I don't know why.

• @MauroALLEGRANZA Oh I couldn't find it. Now what can I do with this post? – siaVash Feb 22 at 15:14

This definition is not good because that way we would get that $$(1,2,2)=(1,2,1)$$. We don't want that to happen.