A385288
Wednesday, June 25, 2025
A385288 - Contribution to the OEIS: Numbers with a prime number of prime factors, counted with multiplicity, and whose prime factors are each raised to a prime exponent

Multiple Dimensions of Time - Part 4
Another article has been published about time existing in multiple dimensions. Gunther Kletetschka recently published Three-Dimensional Time: A Mathematical Framework for Fundamental Physics in Reports in Advances of Physical Sciences, Volume 09, 2025.
Prior posts on this subject include:
Dimensions of time raised in science fiction: Robert Heinlein book, The Pursuit of the Pankera (The Pursuit of the Pankera | Arc Manor Books)
Multiple Dimensions of Time - Part 2:
Dynamical topological phase realized in a trapped-ion quantum simulator | Nature

Monday, June 23, 2025
Vera C. Rubin Observatory
The Vera C. Rubin Observatory, located at an altitude of 2700 m in Chile, recently became operational. The observatory is named for Vera C. Rubin, an American astronomer who pioneered discoveries about galactic rotation rates (this discovery has led to the understanding of dark matter).
Site construction began on 14 April 2015 with the ceremonial laying of the first stone. The first on-sky observations with the engineering camera occurred on 24 October 2024, while system first light images were released 23 June 2025. Images are recorded by a 3.2-gigapixel charge-coupled device imaging (CCD) camera, the largest digital camera ever constructed.
Some of its first released images are below:
Here is a video of asteroids detected by the new telescope: https://www.youtube.com/watch?v=DTuq-vBsDJE&t=45s

Thursday, June 12, 2025
X = 500 (Space X completes 500th mission)

Sunday, June 8, 2025
800,000,000,000 Stars

Friday, June 6, 2025
Famous Mathematicians of Vietnam
Based on available information and their prominence in global mathematics, here are five notable Vietnamese mathematicians:
Ngô Bảo Châu (b. 1972)
Renowned for proving the fundamental lemma for automorphic forms, he became the first Vietnamese to win the Fields Medal in 2010, often regarded as the highest honor in mathematics. His work has had a significant impact on algebraic geometry, and he is a professor at the University of Chicago.
Hoàng Xuân Sính (b. 1933)
A pioneering figure, she was the first female mathematics professor in Vietnam and a student of the influential mathematician Alexander Grothendieck. Her work in mathematics education and research during challenging times, including the Vietnam War, has left a lasting legacy.
Phạm Tuấn Huy
Recognized as the second Vietnamese mathematician to receive a Clay Research Fellowship, following Ngô Bảo Châu. His contributions to mathematics, though less detailed in public records, mark him as an emerging figure in the global mathematical community.
Phan Thanh Nam
Honored in 2020 as the first Vietnamese mathematician to receive a prestigious international award (specific details vary), his work in mathematical physics has gained attention, adding to Vietnam’s growing mathematical reputation.
Lương Thế Vinh (1441–1496)
A historical scholar and mathematician from the Lê dynasty, he is celebrated in Vietnam for his contributions to mathematics education and problem-solving, including the compilation of mathematical texts that influenced Vietnamese scholarship.

Tuesday, June 3, 2025
Famous Brazilian Mathematicians
Brazil has produced many notable mathematicians who have made significant contributions to various fields of mathematics. Below is a list of ten prominent Brazilian mathematicians, based on their recognition, contributions, and impact, as derived from available information. Note that "fame" is subjective, and this list prioritizes those with international recognition, significant awards, or historical importance, while acknowledging that comprehensive data on all Brazilian mathematicians is limited.
1. Artur Avila (b. 1979)
-Field: Dynamical systems, spectral theory, chaos theory.
-Notable Achievements: First Latin American to win the Fields Medal (2014), recognized for his work in dynamical systems. His contributions have brought clarity to the field of chaos theory, earning him global acclaim.
(https://en.wikipedia.org/wiki/Artur_Avila)(https://americasquarterly.org/fulltextarticle/aq-top-5-latin-american-academics-artur-avila/)
(https://twas.org/article/brazilian-artur-avila-wins-twas-lenovo-prize)
-Why Famous: The Fields Medal, often considered the "Nobel Prize of mathematics," marks him as Brazil’s most celebrated contemporary mathematician.
2. Jacob Palis (1940–2025)
- Field: Dynamical systems.
- Notable Achievements: Internationally recognized for his work in dynamical systems, served as president of the International Mathematical Union, and received numerous awards, including the Balzan Prize.
(https://impa.br/en/notices/morre-matematico-jacob-palis-gigante-da-ciencia-brasileira/)
(https://www.famousfix.com/list/21st-century-brazilian-mathematicians)
- Why Famous: A giant in Brazilian science, he held influential roles and mentored many mathematicians.
3. Júlio César de Mello e Souza (1895–1974)
- Field: Mathematics education, recreational mathematics.
- Notable Achievements: Known by his pseudonym Malba Tahan, he wrote *The Man Who Counted*, a popular book blending mathematics with storytelling, widely influential in Brazil and beyond.
(https://proofwiki.org/wiki/Mathematician:Mathematicians/Sorted_By_Nation/Brazil)
(https://www.famousfix.com/list/brazilian-mathematicians)
- Why Famous: His accessible works popularized mathematics in Brazil.
4. Manfredo Perdigão do Carmo (1928–2018)
- Field: Differential geometry.
- Notable Achievements: Renowned for his work in differential geometry, particularly on Riemannian manifolds, and authored influential textbooks used worldwide.
(https://proofwiki.org/wiki/Mathematician:Mathematicians/Sorted_By_Nation/Brazil)
- Why Famous: His textbooks and research contributions have a lasting impact on global mathematics education.
5. Elon Lages Lima (1929–2017)
- Field: Topology, mathematics education.
- Notable Achievements**: A leading figure in Brazilian mathematics, he contributed to topology and wrote numerous textbooks that shaped mathematics education in Brazil.
(https://proofwiki.org/wiki/Mathematician:Mathematicians/Sorted_By_Nation/Brazil)
- Why Famous: His educational contributions made him a household name in Brazilian academia.
6. Paulo Ribenboim (b. 1928)
- Field: Number theory.
- Notable Achievements: Known for his work in number theory, particularly on prime numbers and Fermat’s Last Theorem, and authored several influential books.
(https://proofwiki.org/wiki/Mathematician:Mathematicians/Sorted_By_Nation/Brazil)
- Why Famous: His extensive publications and international career (notably in Canada) brought him recognition.
7. Fernando Codá Marques (b. 1979)
- Field: Differential geometry, geometric analysis.
- Notable Achievements: Recognized for solving major conjectures in geometric analysis, he received the ICTP Ramanujan Prize and other honors.
(https://www.famousfix.com/list/21st-century-brazilian-mathematicians)(https://www.famousfix.com/list/brazilian-mathematicians)
- Why Famous: His groundbreaking work has earned him international acclaim among modern mathematicians.
8. Gauss M. Cordeiro (b. 1952)
- Field: Statistics, probability.
- Notable Achievements: Highly cited for his contributions to statistical distributions and regression models, with significant influence in applied mathematics.
(https://research.com/scientists-rankings/mathematics/br)
- Why Famous: His prolific research output has made him one of Brazil’s most cited mathematicians.
9. José Mario Martínez (b. 1948)
- Field: Optimization, numerical analysis.
- Notable Achievements**: Known for his work in nonlinear optimization and numerical methods, with applications in computational mathematics.
(https://research.com/scientists-rankings/mathematics/br)
- Why Famous: His contributions to optimization have practical and academic impact, particularly in Brazil.
10. Luiz Henrique Jacy Monteiro (1918–1975)
- Field: Algebra, mathematical analysis.
- Notable Achievements**: Played a major role in developing Brazilian mathematics in the mid-20th century, particularly through his work at Brazilian universities.
(https://mathshistory.st-andrews.ac.uk/Biographies/Monteiro/)
- Why Famous: His foundational contributions helped establish modern mathematics in Brazil.
Notes:
- This list is curated based on available sources, prioritizing mathematicians with international recognition (e.g., Fields Medal, major awards) or significant influence in Brazil (e.g., educational impact).
(https://pantheon.world/profile/occupation/mathematician/country/brazil)(https://research.com/scientists-rankings/mathematics/br)(https://proofwiki.org/wiki/Mathematician:Mathematicians/Sorted_By_Nation/Brazil)
- Other notable mathematicians, such as Celso C. Ribeiro, Benar Fux Svaiter, or Welington de Melo, could be included but were less frequently cited in sources for broad fame.
(https://research.com/scientists-rankings/mathematics/br)(https://www.famousfix.com/list/21st-century-brazilian-mathematicians)
Post and graphic created by Grok.
I apologize for the inaccurate depictions in the title graphic. Below are some photos of the featured mathematicians:

Monday, June 2, 2025
1679 - One important message sent from Earth 31 years ago
In 1974 an interstellar radio transmission was broadcast to the globular cluster Messier 13 from the Arecibo radio telescope in Puerto Rico. The message was 1679 bits long. The length of this message was chosen purposely because 1679 is a semiprime with the prime divisors 23 and 73. The message, when plotted in a 23 x 73 array, produces the graphic shown below:
- The numbers one to ten (white; left to right)
- The atomic numbers of the elements hydrogen, carbon, nitrogen, oxygen, and phosphorus, which make up deoxyribonucleic acid (DNA) (purple)
- The formulas for the chemical compounds that make up the nucleotides of DNA (green)
- The estimated number of DNA nucleotides in the human genome, and a graphic of the double helix structure of DNA (white and blue, respectively)
- The dimension (physical height, 5'9") of an average man (blue/white), a graphic figure of a human being (red), and the human population of Earth which was about 4 billion at the time (white)
- A graphic of the Solar System (including Pluto), indicating which of the planets the message is coming from (yellow). The Sun is on the left and the third planet, Earth, raised toward the human figure
- A graphic of the Arecibo radio telescope and the dimension (the physical diameter) of the transmitting antenna dish (purple, white, and blue)this message:

Friday, May 23, 2025
JWST Detects Earliest Formed Galaxies

Friday, May 16, 2025
40,000 Views!
40001 to 40999
- 40320 = smallest factorial (8!) that is not a highly composite number
- 40425 = square pyramidal number
- 40585 = largest factorion[1]
- 40678 = pentagonal pyramidal number
- 40755 = the smallest number >1 to be a Triangular number, Pentagonal number, and a Hexagonal number.[2] Additionally, it's a 390-gonal, 4077-gonal, and 13586-gonal number.[3][4][5]
- 40804 = palindromic square
1. "Sloane's A014080 : Factorions". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation. Retrieved 2016-06-15.
2. "A046180 - OEIS". oeis.org. Retrieved 2024-12-18.
3. Sloane, N. J. A. (ed.). "Sequence A000217 (Triangular numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
4. Sloane, N. J. A. (ed.). "Sequence A000326 (Pentagonal numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.
5. Sloane, N. J. A. (ed.). "Sequence A000384 (Hexagonal numbers)". The On-Line Encyclopedia of Integer Sequences. OEIS Foundation.

Saturday, May 10, 2025
Zero (Part 2)
A prior post had Chat GPT write a blog about zero.
Recently, Scientific America published a similar article: https://www.
I'll leave it to the readers of this blog to say who did a better job summarizing the topic.
Also in this blog about "Zero" was the book review: https://jamesmacmath.blogspot.com/2023/12/book-review-zero-biography-of-dangerous.html.

Thursday, May 8, 2025
Pope Leo XIV - a mathematics major

1679 - One important message sent from Earth 31 years ago
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