Professor Zhang, who is just over 40 years old this year, is one of the first batch of students to go to college after the resumption of the college entrance examination. Being able to sit on the throne of the first mathematics department in China at this age has proven his excellence.

Professor Zhang was admitted to the Department of Mathematics as a primary school teacher and quickly became immersed in the wonderful world of mathematics. After entering Capital University, he began research on finite groups and was awarded the honor for solving an international mathematical problem.

It has attracted widespread attention from the international mathematical community.

Recalling those difficult days made him feel emotional and proud. At that time, there was no computer retrieval system today. If you want to search for the latest research results related to that issue, you can only go through journals one by one. During that time

He read through all the "Algebra" magazines in the past twenty years. This magazine publishes two books every month. In the past twenty years, there have been almost 500 books. This is just one of his reference materials, which is from

Among the magazines stacked higher than him, he found clues to solve this problem.

Although now he has become the head of the Department of Mathematics at Capital University, his work is much busier, and his research on finite groups has reached a critical stage, he still has not given up the habit of reading journals.

"The latest issue of "Annual Review of Mathematics" has been sent!" Professor Zhang sighed. With the strength of the strongest mathematics department in the country, Capital University has only published two articles so far, one of which was eighteen years ago.

, the other article was two years ago. Although there has been some improvement in recent years, Professor Zhang is worried about the future of the Department of Mathematics when he thinks of those good prospects going to the Department of Finance.

Huh? This name seems to be Chinese! Have mathematicians in the Chinese circle achieved great results recently? Professor Zhang quickly turned to Lu Qiujian's paper and scanned the signature part; hey, it's from Princeton, I thought it was

Which university in China?

Hey, Lv-Qiu Jian? This name seems familiar! Professor Zhang immediately put down his paper and flipped through the files in the filing cabinet. He could find the place for the mathematical materials no matter how messy they were. However, even though this kind of administrative information was used by the assistant

It was neatly organized, but he still couldn't figure it out after searching for a long time.

He immediately got up and walked outside and called his assistant, "Quick, help me check some information! What is the name of the student we exchanged to Princeton this year!"

"No need to look it up, I remember it was Lu Qiujian!" The assistant couldn't remember the mathematical formulas clearly, but he had a photographic memory of these things. He couldn't help complaining in his heart. He had offended himself a lot because of this quota.

people.

"Are you sure?" Professor Zhang showed a hint of joy. After tutting twice, he shook his head and said, "You have to be more careful. Go find his file and show it to me!"

"What happened?" The assistant walked towards the cabinet where the information was stored in confusion.

"It's a good thing, it's a good thing!" Professor Zhang looked around, wanting to go back and read Lu Qiujian's papers for a while, but he was afraid that he wouldn't be able to see Lu Qiujian's archives for the first time, so he couldn't help but urge, "Hurry up.

!It still takes so long to find information? How do you usually do your work!"

"It'll be ready soon, it'll be ready soon!", the assistant responded with a smile, while secretly complaining, information like this has always been placed deep in the cabinet, how can there be such a document as "Survey on Housing Situation of Faculty and Staff in Departments"

Important! What happened to Professor Zhang today? He was never so active when dividing houses before!

"Oh! Look for it quickly. If you find it, send it to me right away!" Professor Zhang finally couldn't help but return to the office and read Lu Qiujian's thesis carefully. Xiao Liu is usually very quick. How can he find information today?

I searched for three minutes and couldn't find it!

"What a great article! What a great article!" Professor Zhang tapped his fingers on the table rhythmically and praised while reading Lu Qiujian's paper. He is still in the prime of life. In addition to his own finite group problems, he is also interested in other cutting-edge research.

Followers quickly realized how good Lu Qiujian’s article was.

Hey, I remember that the teacher of partial differential calculus in the college is Professor Ren. Professor Ren’s research direction seems to be different from the problems involved in this paper? Professor Ren’s main research is... and the problem solved in this article

yes...

"Professor Zhang, the information has been found!", the assistant's words interrupted his thoughts, and he looked up and saw a document bag handed over by the assistant.

"Won't you wait a moment! Didn't you see that I was thinking about the problem?" Professor Zhang was very annoyed when he was interrupted by others just after he had figured out a clue.

He opened the document bag several times and took out Lu Qiujian's file. It clearly stated that he would go to Princeton University in the United States for a one-year exchange study this semester.

Didn't you just ask me to send the information as soon as I found it? The assistant didn't dare to argue, so he had to stand there aggrievedly.

It's him! Seeing that the assistant was still around, Professor Zhang ordered, "Go and call Professor Ren and ask him to come to my place right away!"

Immediately again! The assistant was almost allergic to these two words now. When he was about to go out, he saw Professor Zhang waved his hand again and picked up the phone, "Forget it, I can't even find any information. I don't know what to ask for when I call."

Until when! Let me do it. You can go out and remember to close the door!"

You officials are so bad! The assistant is on the verge of tears. The good image he has worked so hard to establish in front of Professor Zhang has been destroyed today!

"Haha, hello, Professor Ren! What are you doing?....Oh, correcting papers!...Let's put the work at hand aside for now! Come to me, I'll show you a paper!" Professor Zhang

Hold back your excitement and send out the invitation.

I wanted to push it off, but seeing Professor Zhang's firm attitude, I put down the paper in my hand and rushed over. When I entered the door, I happened to see Professor Zhang walking around the office with a magazine in his hand.

"Hey! Who has published another paper?" Professor Ren walked over with a smile. This guy came to show off his achievements to me again?

"Huh? Ann.-of-Math!!" Professor Ren was shocked when he saw the cover of the magazine. He couldn't help but read out the English abbreviation of "Annual Review of Mathematics", "Old Zhang! You published an article on it! It's amazing.

!”

"It's not me! It's a student from our school!" Professor Zhang handed the magazine over as he said it. Hey, everything about this article is good, but the word Princeton is a bit awkward. It would be better if it were replaced by Capital University!

"Oh, which exchange student went to Princeton!" Professor Ren still had an impression of the name Lu Qiujian, "You can publish a paper here in just a few months. Is Princeton really so powerful?", No.

, I will find an opportunity to go over and communicate!
Chapter completed!