On the website of the Department of Mathematics and Statistics, Faculty of Science and Technology, Thammasat University, Dr. Paolo Bertozzini has announced that on Monday, 23 November 2020 in Room LC2-230 from 3:30pm to 6pm will be a new session in the Mathematics in Thailand Colloquium.

Ajarn Prapangpong Ponsriiam, Associate Professor of Mathematics at Silpakorn University will speak on Various Problems on Certain Integer Sequences, Arithmetic Functions, and Arithmetic Progressions.

The seminar will be available on-site and online through the Jitsi platform.

Here is Ajarn Prapangpong’s abstract:

Abstract: I will speak about various number-theoretic problems I have worked on, which dealt mostly with the objects in the title. The possible topics are as follows. 1. The divisor function on arithmetic progressions compare with primes in arithmetic progressions, 2. Arithmetic progressions in certain integer sequences, 3. Fibonacci and Lucas numbers, 4. Sums involving the floor function, 5. Other topics.

Although students of mathematics will naturally be most interested in the seminar, it is also a good occasion for students interested in intellectual history and the history of science to learn more about Fibonacci and Lucas numbers.

The Thammasat University Library collection includes a number of books about different aspects of Fibonacci numbers.

In mathematics, the Fibonacci numbers form a sequence such that each number is the sum of the two preceding ones, starting from 0 and 1.

Fibonacci numbers are named after Italian mathematician Leonardo of Pisa, later known as Fibonacci. In a book published in 1202, Fibonacci introduced the sequence to Western European mathematics, although the sequence had been described earlier in Indian mathematics, as early as 200 BC in work on enumerating possible patterns of Sanskrit poetry.

Fibonacci numbers appear unexpectedly often in mathematics, so much so that there is an entire journal dedicated to their study, the Fibonacci Quarterly. Applications of Fibonacci numbers include computer algorithms such as the Fibonacci search technique and the Fibonacci heap data structure, and graphs called Fibonacci cubes used for interconnecting parallel and distributed systems.

They also appear in biological settings, such as branching in trees, the arrangement of leaves on a stem, the fruit sprouts of a pineapple, the flowering of an artichoke, and an uncurling fern.

Fibonacci numbers are also closely related to Lucas numbers.

The French mathematician, François Édouard Anatole Lucas (1842-1891), who gave the series of numbers 0, 1, 1, 2, 3, 5, 8, 13, .. the name the Fibonacci Numbers, found a similar series occurs often when he was investigating Fibonacci number patterns:

2, 1, 3, 4, 7, 11, 18, …

The Fibonacci rule of adding the latest two to get the next is kept, but here we start from 2 and 1 (in this order) instead of 0 and 1 for the (ordinary) Fibonacci numbers.

The Lucas numbers have lots of properties similar to those of Fibonacci numbers.

Thailand and Lucas numbers

All TU students should be particularly interested in François Édouard Anatole Lucas because he published one mathematics discovery using a pen name that suggested he was from Siam.

Lucas invented the Tower of Hanoi puzzle, which he marketed under the nickname N. Claus de Siam (N. Claus from Siam), an anagram of Lucas d’Amiens (Lucas from Amiens).

Lucas had an unusual death. He attended a dinner banquet of the annual meeting of the French Association for the Advancement of Sciences. A waiter dropped some plates on him and a broken piece cut his face. He died a few days later of a severe skin inflammation.

The 23 November event is part of the Thammasat University “Ola Bratteli” Mathematical Physics Seminar and Mathematics in Thailand Colloquium, Dedicated to the memory of Ola Bratteli.

Ola Bratteli was a Norwegian mathematician who taught at the University of Trondheim and the University of Oslo.

The TU Library owns a book by Professor Ola Bratteli.

Operator algebras and quantum statistical mechanics in two volumes is available in the General Stacks of the Puey Ungphakorn Library, Rangsit campus.

In an article posted online, some friends and family members pay tribute to Professor Ola Bratteli:

While he was in Australia, he did not always come home for Christmas. A barbecue on the beach in the sunshine was more tempting than snow, sleet and freezing temperatures. Perhaps he had covered enough distance on skis.

Before Ola moved back to Norway, he was fortunate enough to meet Rungnapa (Wasana). He was to share almost half his life with her. Kitidet – his son – was his pride and joy. Rungnapa and Ola travelled widely all over the world. There were holidays, but she also accompanied him to conferences and on visits to universities. After a while, they settled down in Norway. They enjoyed good years together. In the last years of his life, Ola’s health deteriorated. Rungnapa was enormously supportive and did all she could to make it possible for him to live at home as long as possible. He was a lucky man. Now Rungnapa and Kitidet have moved back to Phitsanulok in Thailand. Ola and Rungnapa built a house in her home city several years ago and had no doubt planned to spend the winters there eventually. It did not turn out that way. Ola died so early. But outside the house there is a small temple for Ola. So in a way he is there too…

Ola had a long connection and affection for Thailand making regular visits – his wife for more than 30 years Wasana was from Phitsanulok. In 2016, Paulo Bertozzini initiated at Thammasat University in Bangkok, the Ola Bratteli Mathematical Physics and Mathematics in Thailand Colloquium when I was honoured to give the first talk.

Ola had a generous spirit and integrity. We will miss his presence and friendship.

The speaker at the 23 November event, Ajarn Prapanpong, earned Bachelor of Science (Mathematics) and Master of Science (Mathematics) degrees from Chulalongkorn University, followed by a Ph.D. in Mathematics from Pennsylvania State University.

Ajarn Prapanpong has received the Paul Bruckman Prize from the Fibonacci Association for the best article and the best presentation in the 18th International Conference on Fibonacci Numbers and Their Applications held at Dalhousie University in Halifax, Nova Scotia, Canada in 2018.

In addition to a website about his research interests, Ajarn Prapanpong maintains a YouTube channel for online teaching and other mathematical updates, a list of other mathematics-related activities,and a site about arts and entertainment, especially music:

The music I like is from the video games produced by Square Soft (Square Enix). Especially, the music from Final Fantasy, Chrono Trigger, Romancing Saga, Seiken Densetsu Legend of Mana is always in my mind.

I did not know the names of the composers at that time but now that the internet is widely used, I know their names. They are Nobuo Uematsu, Yasunori Mitsuda, Kenji Ito, Hiroki Kikuta, and Yoko Shimamura.

(All images courtesy of Wikimedia Commons)