Its Own Inverse on Six Elements
Difficulty: Hard · Topics: Discrete Mathematics, Functions, Function Combinatorics
Olti elementda o‘z-o‘ziga teskari
Let X=\1, 2, …, 6\. How many functions f:X→ X satisfy fbig(f(x)big)=x for every x?
X=\1, 2, …, 6\ bo‘lsin. Nechta f:X→ X funksiya har bir x uchun fbig(f(x)big)=x ni qanoatlantiradi?