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Hi Everyone,

I am a hedgehog who likes Message Board halping, funny pictures, emoji wars, and AoPS Wiki contributions. Keep these fun things coming!

This hedgehog represents my attitude towards mathematics--victorious and enthusiastic!

Commander Hedgehog.png

And here is my personified self-portrait:



AoPS Bio

Jerry graduated from Northeastern University in 2018 as a mathematics and computer science combined major. He has eleven years of experience working with students. He has served as an AoPS instructor and a message board moderator since 2019. During his last two years in high school, he served as the math club president and prepared lively lectures on contest math. As a result, he inspired many kids to get interested in math and participate in math competitions (such as AMC and ARML). For the last eight years, he has worked with Math League to write math contests for students from grades 4 through 12 in the USA. In his mind, nothing is more rewarding than educating tomorrow’s bright minds. In 2020 he published the book English-Chinese Mathematics Encyclopedia: Algebra, Geometry, and Pre-Calculus in Tsinghua University Press in China. In his spare time, he loves contributing to the AoPS Wiki and playing chess and all sorts of board games, especially Scotland Yard, and Samurai.

AoPS Wiki Contributions

Below are my contributions to the AMC/AIME Problems' Solutions in the AoPS Wiki. I understand that in this communal Wiki, we all have to collaborate and make compromises. In any of my solutions, if you find flaws and/or want major revisions, then please contact me via my user talk page or the private messaging system before you take action. I am sure that we can work things out.

Thank you for your cooperation, and hope you enjoy reading my solutions.

Finally, here is my YouTube channel (MRENTHUSIASM) for the video solutions. Go ahead and subscribe--you know you want to. $\smiley{}$



AMC 10



AoPS Forums


Let's have a good time in this forum. Feel free to discuss math classes, math competitions, AoPS Wiki contributions, funny pictures, emojis, and ... HEDGEHOGS! $\smiley{}$

Hedgehog LALALALALA.gif


English-Chinese Mathematics Encyclopedia: Algebra, Geometry, and Pre-Calculus (Tsinghua University Press in Beijing, China)

English-Chinese Mathematics Encyclopedia.jpeg


In this section, I will show you my artworks of certificates and posters. Hope you enjoy them! $\smiley{}$

I especially thank Flame Kho for teaching me how to use the Chuangkit design platform.

Hall of Fame in MATHCOUNTS/AMC 8 Basics (2557)

2021 AMC 8 Perfect Scorers.png

2557 Gold.png

2557 Silver.png

2557 Bronze.png

Hall of Fame in MATHCOUNTS/AMC 8 Basics (2786)

2846 2022 AMC 8 Perfect Scorers.png

2846 Gold.png

2846 Silver.png

2846 Bronze 1.png

2846 Bronze 2.png

Hall of Fame in MATHCOUNTS/AMC 8 Basics (3011)

We will see about that--designing templates now ...

Most Prominent Member of Boston Xiangqi Community

Funny Guy.png


As you might know, I am particularly fond of cats. My family has raised more than ten cats. These little angels are so adorable! MEOW MEOW MEOW!!! 🐱🐱🐱



Kidney Bean

Kidney Bean 1.jpg   Kidney Bean 2.jpg

Jin Bao

Jin Bao.jpg

Gray Gray

Little Gray Gray 1.jpg

Little Gray Gray 2.jpg   Little Gray Gray 3.jpg

External Links

  • User Talk Page
    Welcome to my user talk page here. Feel free to leave any message you like.
  • Flame Kho's User Page
    Recently I am helping my friend Flame Kho to create his user page. Enjoy his AMC Solutions and artworks! $\smiley{}$
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