From f026b7a3ad67e727bac35edb8a4fdd4177a4a10c Mon Sep 17 00:00:00 2001
From: FidelSch <honoratofidel@gmail.com>
Date: Wed, 3 Dec 2025 16:41:13 -0300
Subject: [PATCH] seq: calculate number length more efficiently

---
 src/uu/seq/src/seq.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/uu/seq/src/seq.rs b/src/uu/seq/src/seq.rs
index 7b56c26f5..b67543e92 100644
--- a/src/uu/seq/src/seq.rs
+++ b/src/uu/seq/src/seq.rs
@@ -290,8 +290,8 @@ fn fast_print_seq(
     // Format the first number.
     let first_str = first.to_string();
 
-    // Makeshift log10.ceil
-    let last_length = last.to_string().len();
+    // Approximate length of the last number in base 10.
+    let last_length = (last.bits() as f64 / std::f64::consts::LOG2_10).ceil() as usize;
 
     // Allocate a large u8 buffer, that contains a preformatted string
     // of the number followed by the `separator`.