From 5c6ad569c4e6be521b8dc41f063a59ff0b02a2cd Mon Sep 17 00:00:00 2001
From: yenru0 <yenru0604@gmail.com>
Date: Wed, 25 Mar 2026 03:49:18 +0900
Subject: [PATCH] complete 2921.rs

---
 storage/zeta/rs/completed/2921.rs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)
 create mode 100644 storage/zeta/rs/completed/2921.rs

diff --git a/storage/zeta/rs/completed/2921.rs b/storage/zeta/rs/completed/2921.rs
new file mode 100644
index 0000000..678ff3e
--- /dev/null
+++ b/storage/zeta/rs/completed/2921.rs
@@ -0,0 +1,14 @@
+use std::io::{read_to_string, stdin};
+
+fn main() {
+    let temp = read_to_string(stdin()).unwrap();
+    let mut iter = temp
+        .split_ascii_whitespace()
+        .map(|x| x.parse::<usize>().unwrap());
+    let n = iter.next().unwrap();
+    let mut s = 0;
+    for i in 1..=n {
+        s += 3 * (i + 1) * i / 2;
+    }
+    println!("{}", s);
+}