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Hack The Box write up for Tabby

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Hack The Box write up for Tabby

Tabby [https://www.hackthebox.eu/home/machines/profile/259] is a box on Hackthebox.eu. It was a ton of fun and I learned a lot about Tomcat and LXD. This box was hard for me because I'm a novice. I ended up needing help from the HackTheBox

Hack The Box write up for Remote

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Hack The Box write up for Remote

This is my guide to hacking the remote [https://www.hackthebox.eu/home/machines/profile/234] box over at Hack The Box [http://hackthebox.edu]. Getting the user flag was very time consuming. There were a lot of little steps that need to all go right. Getting root was above

Hack the Box write up for Devel

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Hack the Box write up for Devel

I've been doing some ethical hacking lately. This is my first writeup for one of the computers I hacked into (legally.) The machine I compromised is called Devel [https://www.hackthebox.eu/home/machines/profile/3] on Hackthebox.eu [http://hackthebox.edu]. I'm a beginner when

Hack The Box write up for Traceback

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Hack The Box write up for Traceback

This was a great box! This article is my guide for hacking traceback, one of the retired machines at HackTheBox.eu [http://hackthebox.eu]. This is my first hacking guide, so hopefully i'm doing this correctly. I enjoyed this box. It was right at my skill level and

Stunning sunset in downtown Austin, TX

Stunning sunset in downtown Austin, TX

I took this photo from my balcony. I used my iPhone XS (which takes pretty great photos.)

The Infinite Monkey Theorem

big numbers Featured

The Infinite Monkey Theorem

The infinite monkey theorem is a bar [http://www.theinfinitemonkeytheorem.com/] in Austin, TX, but it is also a very cool mathematical theorem that deals with very big numbers. This article is about the theorem which has become very popular in recent times. The theorem as I understand it is

1+2+3+4+... = -1/12

1+2+3+4+... = -1/12

This is a remarkable and hard to believe consequence in mathematics. If you were to sum the natural numbers all the way to infinity, you would get \(-\frac{1}{12}\). $$ 1+2+3+4+5+6... = -\frac{1}{12} $$ This is just insane. It makes no sense that

Graham's number - big numbers blow my mind!

Graham's number - big numbers blow my mind!

One of the most famous big numbers in mathematics is Graham's number. For a while it was the largest number ever used in a legit mathematical proof. That isn't the case anymore but it is still a legend. The number is the upper bound to a

The longest finite time ever calculated by a physicist

The longest finite time ever calculated by a physicist

I've written quite a bit on big numbers [https://josh.kerr.dev/tag/big-numbers/] because I find them fascinating. Two of the areas where you find interesting big numbers are astronomy and cosmology. For example the observable universe is thought to be 93 billion light years across (That&

The Ackermann function explained

The Ackermann function is a recursive function originally invented by Wilhelm Ackermann [https://en.wikipedia.org/wiki/Wilhelm_Ackermann]. It is one of a series of mathematical functions that quickly generates enormous numbers. If you haven't read my article on Knuth's up arrow notation [http://www.

Knuth's up arrow notation explained

When we talk about large numbers, we are talking about numbers that are bigger than what we use in our ordinary day to day life. These are numbers typically used by mathematicians in fields such as cosmology, cryptography and statistical mechanics. Since big numbers have a lot of digits, it

How big is googol?

Googol is a big number. The search engine was famously named after it. There are several ways that we can think about Googol. Written with exponents, the number can be represented like so: $$ 10^{100} $$ If you expand it out you would write a 1 followed by 100 zeros: 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

Getting Started

Welcome to Ghost

You're live! Nice. We've put together a little post to introduce you to the Ghost editor and get you started. You can manage your content by signing in to the admin area at <your blog URL>/ghost/. When you arrive, you can select this