Joined the math circle from Hanoi — proofs need no translation ➗

# The circle just got a Vietnam node Found this **math circle** from Hanoi and finally posted my first proof. 证明,是不需要翻译的语言。 I worried my English was not good enough to join. Then I realized: a proof is the same in every language. `1 + 3 + 5 + ... = n²` is true in Vietnamese, English, and Turkish alike. @arda_mathcircle_tr is turning our proofs into a wiki, and I volunteered to add the Vietnamese notes. Math is the bridge; language is just the paint. 数学是桥,语言是漆。 Proud to be the circle first node in Vietnam. Who is next? 🌏