Chapter 41 Accidentally encountered a world problem

Of course it would take a certain amount of time for Teacher Xu to come up with questions, so Lin Xiao continued to read her book.

Time passed quickly, and when it was about nine o'clock in the evening, Lin Xiao checked the time. When it was time to return to the hotel, he stretched himself, then started to clear the table and prepare to go back.

When he walked to the door, he remembered that Teacher Xu said that he would give him some difficult questions. However, it seemed that Teacher Xu had just left the study room because of something and had not returned yet.

However, he should have already solved the problem, right?

So Lin Xiao walked to the podium and took a look. There were indeed several pieces of paper with titles written on them.

In addition, there is a pile of scratch paper, which is full of various styles. There are quite a lot of them, but many of them have big crosses drawn on them.

"Did Teacher Xu encounter a problem?"

Lin Xiao thought for a moment, but then he didn't care anymore and picked up the pieces of scratch paper with the titles written on them.

He briefly browsed the first piece of paper. There were questions on both sides, four in total, and they were basically all advanced algebra questions, including determinants, matrices, and other categories.

Then he quickly looked at the next two papers. The second paper also had four questions, but the third paper only had one question. Lin Xiao didn't care what the question was, as long as it wasn't manuscript paper.

Then he found a piece of paper from the side and wrote on it [Teacher Xu, I took the questions you asked and will come back to you tomorrow night - Lin Xiaoliu].

Then, he left the classroom.

Not long after, Xu Hongbing came back. He walked to the podium and saw the note left by Lin Xiao. He smiled slightly. He had racked his brains to come up with those questions, and some of them included some of the questions he had given for mathematics competitions before. .

He wanted to see if Lin Xiao could write it.

He even looked forward to tomorrow night when this boy would come and cry to him that it was too difficult and he couldn't do it.

Shaking his head and not thinking more, he turned over the table top again.

He doesn't have nothing to do when he stays here. As a mathematics professor, he is also studying some problems.

For example, recently, he has been studying a world-class problem, that is, whether there are infinitely many prime numbers in the Fibonacci sequence.

The problem of prime numbers has always been discussed in the mathematical community. The famous Riemann Hypothesis, Goldbach's Hypothesis, Twin Prime Conjecture, Mersenne Prime Distribution, etc. are all related to prime numbers.

Although this kind of purely numerical game does not seem to be of much use, it has also attracted constant discussion by pure mathematicians.

The question of whether there are infinitely many prime numbers in the Fibonacci sequence discussed by Xu Hongbing is not as famous as the Mersenne prime numbers, but if the proof is completed, it will definitely cause a shock in the mathematics world and be of great use to him.

For example, the student Liu who proved Sitapan's conjecture later graduated and was directly hired as a full professor at Nanzhong University at the age of 22. So if Xu Hongbing can complete the proof, what benefits can he get? That is unknown, especially since the field of number theory to which this problem belongs is a field that many mathematicians are paying close attention to.

But obviously, he had been studying for many days and still had no clue. The wasted scraps of draft paper on the desk in front of him proved how much effort he had spent.

However, Xu Hongbing's problem now is not how to prove this problem, but, what about his question?

After looking for the paper on his desk, he found that his piece of paper with the Fibonacci sequence written on it and asked if there were infinitely many prime numbers was missing.

Where did his question go?

Is it possible...

Xu Hongbing thought of a funny thing. Lin Xiao wouldn't think it was his question and take it away, right?

It's really possible.

Shaking his head, just think of it as a 'surprise' for Lin Xiao.

Oh no, it should be 'frightened'.

Of course, the premise is that Lin Xiao can write there.

He came up with eight difficult questions that he was very satisfied with. The first four questions can definitely become the finale questions in the college advanced algebra exam, and the last four questions are definitely competition-level questions, and they are also the kind of mathematics majors. , if Lin Xiao could finish it all before tomorrow night's self-study, he would eat the desk in front of him.

Along with those scratch papers.

When Lin Xiao didn't make it, he came to him. He just comforted Lin Xiao that it was okay, taught him that this showed the importance of having a teacher, and then persuaded him that after going to college, he must study hard with the teacher and not work behind closed doors. .

I believe that Lin Xiao will also follow his guidance by then, and the conditions will definitely be more limitless in the future.

Thinking of his plan, Xu Hongbing nodded with satisfaction. He must be a good teacher.

Then, he stopped thinking about it, found another scrap of paper, wrote down the expression of the Fibonacci sequence, and then added another one at the end [Are there infinitely many prime numbers? 】

Then he started trying to solve the problem again.

…

Hotel, in Lin Xiao's room.

"Well, there's something interesting about the questions this teacher asked. It's really difficult."

Lin Xiao looked at the questions Xu Hongbing gave him and fell into thinking.

He had already finished writing the four questions on the first piece of paper, and now he was writing on the second piece of paper. However, because the difficulty suddenly increased a lot, he felt the difficulty for a while.

If he knew that this question was completely qualified as a question for the college mathematics professional competition, he would not be so entangled, because when he faced this kind of problem, he also needed a certain amount of time to think about it. After all, the depth and breadth of college mathematics, There are also certain requirements for students in terms of knowledge.

So, it took him about five minutes to finally come up with an idea.

"It took me five minutes, which is outrageous."

Shaking his head, he then began to write based on the ideas he had come up with.

That's right, for him, five minutes is already a certain level of difficulty. Otherwise, like the question Xu Hongbing asked him during self-study just now, he only took one minute to solve it, and it took more than three points. All species are difficult.

"what are you doing?"

At this time, Kong Huaan, who was also studying on the other side, asked him.

But Lin Xiao was so immersed that she didn't notice what he said.

Seeing that Lin Xiao didn't reply, Kong Huaan couldn't help but curiously came to Lin Xiao's side and took a look.

After reading it, he went back silently.

Sure enough, he should just be a hacker. Mathematics is not something he should consider.

Time passed quickly and it was half past eleven.

Lin Xiao, who had been busy working on the questions, finally breathed a sigh of relief and put down the second piece of paper.

Looking at the time, Lin Xiao couldn't help but feel that Xu Hongbing's ability to pose questions was really great.

It actually took him an hour and a half to finish these eight questions. The first four questions only took him 20 minutes, and the last four questions actually took him 70 minutes.

In particular, these questions seemed to be randomly asked by Xu Hongbing.

Being able to ask so many difficult questions casually is not something that any teacher can do.

“But I finally finished it, and it’s worthy of me.”

Lin Xiao sighed in his heart, and then picked up the third piece of paper.

That piece of paper with only one question on it.

I saw it read: [The first two terms of the fate sequence Fn are both 1. Assume Fn3=Fn1+Fn2. Is there an infinite number of prime numbers in the sequence Fn? 】

Every time I refresh the background and see recommendations, I feel motivated to code.

Three updates today