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		<id>https://www.explainxkcd.com/wiki/index.php?title=3137:_Cursed_Number&amp;diff=409634</id>
		<title>3137: Cursed Number</title>
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				<updated>2026-04-04T20:15:08Z</updated>
		
		<summary type="html">&lt;p&gt;2800:810:503:8182:1027:A7A4:6866:51D2: link glitch&lt;/p&gt;
&lt;hr /&gt;
&lt;div&gt;{{comic&lt;br /&gt;
| number    = 3137&lt;br /&gt;
| date      = September 3, 2025&lt;br /&gt;
| title     = Cursed Number&lt;br /&gt;
| image     = cursed_number_2x.png&lt;br /&gt;
| imagesize = 388x449px&lt;br /&gt;
| noexpand  = true&lt;br /&gt;
| titletext = Another group of mathematicians is working to put an upper bound on the number, although everyone keeps begging them to stop.&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
==Explanation==&lt;br /&gt;
&lt;br /&gt;
It is quite common on mathematics to not know the value (or existence) of a number but be able to put bounds on it. For example, we know the first counterexample to the {{w|Collatz conjecture}} is at least 10^21, if it exists. There are also constants where we have an upper bound.&lt;br /&gt;
&lt;br /&gt;
In this case, there is apparently postulated to exist a number that extremely harmful to the human mind to read it without eye protection - an {{w|information hazard}}. Dangerous pieces of writing like this are a fairly common trope in speculative fiction, such as the {{w|Necronomicon}} in the {{w|Cthulhu Mythos}}, [https://wiki.teamfortress.com/wiki/Bombinomicon The Bombinomicon] in Team Fortress 2 (a Joke on the Necronomicon), [https://scp-wiki.wikidot.com/scp-033 cognitohazards] in the {{w|SCP Foundation}}, the Basilisk in {{w|BLIT_(short_story)|BLIT}} by David Langford, and {{w|Monty Python}}'s {{w|The Funniest Joke in the World|Funniest Joke in the World}}. It is also very similar to the concept of an {{w|illegal number}}, or the {{w|Number of the beast}}.&lt;br /&gt;
&lt;br /&gt;
Saying that it is once ''again'' safe to view large random numbers without eye protection may imply that the cursed number used to not be cursed (as opposed to no one realizing that the cursed number existed). This might indicate an evolutionary change in human brain structure, or, [[2332: Cursed Chair|considering previous comics]], someone with magical powers literally placing a curse on it (but not telling humans which). In the latter case, the fact that mathematicians have been able to place a lower bound might suggest that the magic-wielder gave some sort of hint, such as a hashed or encrypted version or a mathematical puzzle/riddle.  Alternatively it could be that after the existence of the cursed number was discovered, but before there was a lower bound on it, people were advised to wear eye protection when viewing any large number, because no one could be sure which large number was cursed.  The mechanism by which the eye protection works is not explained; theoretically any eye protection which allowed someone to view the cursed number at all shouldn't work, as being able to see or read the number means you can perceive it.&lt;br /&gt;
&lt;br /&gt;
Naturally, the mathematicians of this world are doing their best, in the interest of public safety, to keep this number away from as many human eyeballs as possible. Through some process they have figured out the number is at least 22 digits long. Numbers this large (greater than 10&amp;lt;sup&amp;gt;21&amp;lt;/sup&amp;gt;, i.e. at least a {{w|Orders_of_magnitude_(numbers)#1021|'sextillion'}}) are extremely unlikely to be found in the day-to-day lives of non-mathematicians (and almost all mathematicians); even if a person spent their entire lives looking at random strings of 22 digit numbers flashing by every millisecond, for a 100 year lifetime, they would still only have about 3 in a (short) billion chance of seeing the number. Because of the low risk, public officials have deemed it safe for people to go about their daily lives reading numbers again without eye protection, which apparently protects you from the number.&lt;br /&gt;
&lt;br /&gt;
Despite this, there are some instances of large numbers (more than 21 decimal digits) that may be encountered relatively frequently. IT professionals may encounter &amp;quot;{{w|Universally unique identifier}}s&amp;quot;.  These are 128 {{w|bit}} binary numbers requiring up to 39 decimal digits to display. However, with 2^128 possible possible numbers of that length, even if you look at UUIDs all day long you are extremely unlikely to see this &amp;quot;cursed number&amp;quot; if it exists.&lt;br /&gt;
&lt;br /&gt;
In the title text another group of mathematicians are trying to narrow down the number's identity even further. The more attributes of the cursed number the mathematicians identify, the easier it is for someone with morbid curiosity or someone researching more attributes of the number to discover the number themselves and get their mind damaged. This includes the researchers themselves, as they are now willingly going above the lower safe limit, increasing their chances of encountering it accidentally. Furthermore, the cursed number may appear as part of another number; for example, 223 appears as part of 2237. Worse, if the number could be determined in some controllable way that didn't necessarily expose its discoverers, it {{w|BLIT (short story)|might be used as a weapon}}, and this might be easier with the upper bound discovered, if the method used to find the number is brute force. This echoes concerns about knowledge gained from research on nuclear forces having been used to create atomic weapons. This was also how the Funniest Joke in the World was used in Monty Python.&lt;br /&gt;
&lt;br /&gt;
==Transcript==&lt;br /&gt;
:[A large screen with one equation in the middle is shown to the left of three people. The left part of the equation shows a black bar with a skull in the middle:]&lt;br /&gt;
: 💀 &amp;gt; 2.6 x 10&amp;lt;sup&amp;gt;21&amp;lt;/sup&amp;gt;&lt;br /&gt;
&lt;br /&gt;
:[Cueball is standing to the right of the screen and further right is Blondie. Blondie is standing behind a lectern with a label in front. Hairbun stands further and holds a paper up in front of her using both hands. The paper shows illegible text surrounding what is visibly the same equation as appears on the screen, with a skull, but not the black bar. None of the text can be read and the skull can only be made out as such, knowing what it is from the screen.]&lt;br /&gt;
:[The lectern reads:]&lt;br /&gt;
:Math Dept&lt;br /&gt;
&lt;br /&gt;
:[Caption below the comic:]&lt;br /&gt;
:Good news: Mathematicians have put a new lower bound on the '''Cursed Number that destroys the minds of all who perceive it'''!&lt;br /&gt;
:It's at least 22 digits, which means it's unlikely to be seen by any human no matter how many random numbers they look at.&lt;br /&gt;
:They say it's once again safe to view large random numbers without eye protection.&lt;br /&gt;
&lt;br /&gt;
{{comic discussion}}&amp;lt;noinclude&amp;gt;&lt;br /&gt;
&lt;br /&gt;
[[Category:Comics featuring Cueball]]&lt;br /&gt;
[[Category:Comics featuring Blondie]]&lt;br /&gt;
[[Category:Comics featuring Hairbun]]&lt;br /&gt;
[[Category:Math]]&lt;br /&gt;
[[Category:Comics with cursed items]]&lt;/div&gt;</summary>
		<author><name>2800:810:503:8182:1027:A7A4:6866:51D2</name></author>	</entry>

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