From b7610cfdcd6a45ce05b4739f13c3c6d8a1282c53 Mon Sep 17 00:00:00 2001
From: Flancian <0@flancia.org>
Date: Thu, 11 May 2023 21:00:21 +0200
Subject: [PATCH] autopushed

---
 406.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/406.md b/406.md
index e8cc61eda..42828f37c 100644
--- a/406.md
+++ b/406.md
@@ -2,3 +2,4 @@
 - I think the fact that 405 and 406 are adjacent in the number line and have wildly differing difficulties of factorization probably says something about the nature of numbers? analyzing this fact can probably lead to interesting relations
 - [[203]] * 2 but then I'm stumped, 203 could be a prime. I hope it is, maybe?
 - It's clearly not divisible by 3 if you already checked [[406]] (sum of digits 10, not divisible by 3), but I still checked out of custom. While doing this, remembering which numbers you don't have to check is useful as it prevents duplicate work. Still I'm not concerned about repeating checks because I enjoy them.
+- There is a bound for possible divisors we have to check; the bound is the square root of 203. That means that we may have gained some equity by not having taken the square root of 406, potentially harder to calculate than that of 203.