D. D. Wall
Encyclopedia
Donald Dines Wall was a mathematician
Mathematician
A mathematician is a person whose primary area of study is the field of mathematics. Mathematicians are concerned with quantity, structure, space, and change....

 working primarily on number theory
Number theory
Number theory is a branch of pure mathematics devoted primarily to the study of the integers. Number theorists study prime numbers as well...

. He obtained his Ph.D.
Doctor of Philosophy
Doctor of Philosophy, abbreviated as Ph.D., PhD, D.Phil., or DPhil , in English-speaking countries, is a postgraduate academic degree awarded by universities...

 on normal number
Normal number
In mathematics, a normal number is a real number whose infinite sequence of digits in every base b is distributed uniformly in the sense that each of the b digit values has the same natural density 1/b, also all possible b2 pairs of digits are equally likely with density b−2,...

s from University of California, Berkeley
University of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...

 in 1949, where his adviser was Derrick Henry Lehmer
Derrick Henry Lehmer
Derrick Henry "Dick" Lehmer was an American mathematician who refined Édouard Lucas' work in the 1930s and devised the Lucas–Lehmer test for Mersenne primes...

. His better known papers include the first modern analysis of Fibonacci sequence modulo
Modular arithmetic
In mathematics, modular arithmetic is a system of arithmetic for integers, where numbers "wrap around" after they reach a certain value—the modulus....

 a positive integer.

Drawing on Wall's work, Zhi-Hong Sun
Zhi-Hong Sun
Sun Zhihong is a Chinese mathematician, working primarily on number theory, combinatorics, and graph theory.Sun and his twin brother Sun Zhiwei proved a theorem about what are now known as the Wall-Sun-Sun primes that guided the search for counterexamples to Fermat's last theorem.-External links:*...

 and his twin brother Zhi-Wei Sun
Zhi-Wei Sun
Zhi-Wei Sun is a Chinese mathematician, working primarily on number theory, combinatorics, and group theory. Currently he works as a professor in Nanjing University....

 proved a theorem about what are now known as the Wall-Sun-Sun prime
Wall-Sun-Sun prime
In number theory, a Wall–Sun–Sun prime or Fibonacci–Wieferich prime is a certain kind of prime number which is conjectured to exist although none are known.- Definition :...

s that guided the search for counterexamples to Fermat's last theorem
Fermat's Last Theorem
In number theory, Fermat's Last Theorem states that no three positive integers a, b, and c can satisfy the equation an + bn = cn for any integer value of n greater than two....

.

Early life

Wall was born in Kansas City, Missouri
Kansas City, Missouri
Kansas City, Missouri is the largest city in the U.S. state of Missouri and is the anchor city of the Kansas City Metropolitan Area, the second largest metropolitan area in Missouri. It encompasses in parts of Jackson, Clay, Cass, and Platte counties...

 on August 13, 1921 to Donald F. Wall and Mary Wooldridge. The family lived in Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...

 and Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

 as he was growing up. In 1933, they moved to Whittier, California
Whittier, California
Whittier is a city in Los Angeles County, California about southeast of Los Angeles. The city had a population of 85,331 at the 2010 census, up from 83,680 as of the 2000 census, and encompasses 14.7 square miles . Like nearby Montebello, the city constitutes part of the Gateway Cities...

, then in 1936 to Santa Barbara, California
Santa Barbara, California
Santa Barbara is the county seat of Santa Barbara County, California, United States. Situated on an east-west trending section of coastline, the longest such section on the West Coast of the United States, the city lies between the steeply-rising Santa Ynez Mountains and the Pacific Ocean...

 where he graduated from High School in 1938. He enrolled at UCLA
University of California, Los Angeles
The University of California, Los Angeles is a public research university located in the Westwood neighborhood of Los Angeles, California, USA. It was founded in 1919 as the "Southern Branch" of the University of California and is the second oldest of the ten campuses...

 and joined the Delta Sigma Phi
Delta Sigma Phi
Delta Sigma Phi is a fraternity established at the City College of New York in 1899 and is a charter member of the North-American Interfraternity Conference. The headquarters of the fraternity is the Taggart Mansion located in Indianapolis, Indiana...

 fraternity.

In April 1940 he had a successful operation to remove a brain tumor at UC Hospital in San Francisco. The surgeon was Howard C. Naffziger
Howard Christian Naffziger
Howard Christian Naffziger was a reputed U.S. neurosurgeon, noted for his invention of the orbital decompression procedure, to alleviate intraocular pressure .-Further reading:* from UCSF...

, who later served on the board of Regents of the University of California. He and Naffziger kept in touch for many years afterwards.

Career

He graduated from UCLA with a B.A.
Bachelor of Arts
A Bachelor of Arts , from the Latin artium baccalaureus, is a bachelor's degree awarded for an undergraduate course or program in either the liberal arts, the sciences, or both...

 in Mathematics in the spring of 1944. After graduation he took a full-time job with Douglas Aircraft but continued in graduate school at UCLA.

In 1946 he received an M.A.
Master of Arts (postgraduate)
A Master of Arts from the Latin Magister Artium, is a type of Master's degree awarded by universities in many countries. The M.A. is usually contrasted with the M.S. or M.Sc. degrees...

 in mathematical statistics from UCLA. In the same year he passed the first three of eight acturial exams.

In 1947, he moved to Hartford, Connecticut
Hartford, Connecticut
Hartford is the capital of the U.S. state of Connecticut. The seat of Hartford County until Connecticut disbanded county government in 1960, it is the second most populous city on New England's largest river, the Connecticut River. As of the 2010 Census, Hartford's population was 124,775, making...

 to work for the Aetna Life Insurance Company. He also taught an evening math class at Trinity College
Trinity College (Connecticut)
Trinity College is a private, liberal arts college in Hartford, Connecticut. Founded in 1823, it is the second-oldest college in the state of Connecticut after Yale University. The college enrolls 2,300 students and has been coeducational since 1969. Trinity offers 38 majors and 26 minors, and has...

.

In the fall of 1947, he returned to graduate school at Harvard University
Harvard University
Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...

, where he became interested in number theory. He also took a class at Massachusetts Institute of Technology
Massachusetts Institute of Technology
The Massachusetts Institute of Technology is a private research university located in Cambridge, Massachusetts. MIT has five schools and one college, containing a total of 32 academic departments, with a strong emphasis on scientific and technological education and research.Founded in 1861 in...

.

In June 1948 he returned to California to complete his Ph.D.
Ph.D.
A Ph.D. is a Doctor of Philosophy, an academic degree.Ph.D. may also refer to:* Ph.D. , a 1980s British group*Piled Higher and Deeper, a web comic strip*PhD: Phantasy Degree, a Korean comic series* PhD Docbook renderer, an XML renderer...

 at UC Berkley, where he also taught classes as a teaching assistant
Teaching assistant
A teaching assistant is an individual who assists a professor or teacher with instructional responsibilities. TAs include graduate teaching assistants , who are graduate students; undergraduate teaching assistants , who are undergraduate students; secondary school TAs, who are either high school...

.

In 1949 he was awarded his Ph.D. in normal number
Normal number
In mathematics, a normal number is a real number whose infinite sequence of digits in every base b is distributed uniformly in the sense that each of the b digit values has the same natural density 1/b, also all possible b2 pairs of digits are equally likely with density b−2,...

s from UC Berkeley.

In fall of 1949 he and his family moved to Santa Barbara
Santa Barbara, California
Santa Barbara is the county seat of Santa Barbara County, California, United States. Situated on an east-west trending section of coastline, the longest such section on the West Coast of the United States, the city lies between the steeply-rising Santa Ynez Mountains and the Pacific Ocean...

 where he took a job as instructor in mathematics at Santa Barbara College of the University of California
University of California, Santa Barbara
The University of California, Santa Barbara, commonly known as UCSB or UC Santa Barbara, is a public research university and one of the 10 general campuses of the University of California system. The main campus is located on a site in Goleta, California, from Santa Barbara and northwest of Los...

. He taught general astronomy
Astronomy
Astronomy is a natural science that deals with the study of celestial objects and phenomena that originate outside the atmosphere of Earth...

 as well as number theory
Number theory
Number theory is a branch of pure mathematics devoted primarily to the study of the integers. Number theorists study prime numbers as well...

 and other math courses. After two years, he was promoted to assistant professor.

In 1950, he taught a course in computer mathematics
Computer mathematics
Computer mathematics could refer to:* Scientific computing - constructing numerical solutions and using computers to analyse and solve scientific and engineering problems...

 at Naval Air Station Point Mugu
Naval Air Station Point Mugu
Naval Base Ventura County Point Mugu or NBVC Point Mugu is a military airbase located in Point Mugu, Ventura County, California, United States. Due to realignment actions which occurred in 2000, the base is now part of Naval Base Ventura County , a consolidated organization that also includes...

, where computers were being developed for calculating missile trajectories.

From his work at Pt Mugu, he was recruited by IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...

 to work as an Applied Science Representative starting July 1951 in Los Angeles
Los Ángeles
Los Ángeles is the capital of the province of Biobío, in the commune of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123,445 inhabitants...

. In 1956, he became IBM's Education Coordinator for the west coast. He traveled to interested universities in the western US to give them details of a program developed by the UCLA Anderson School of Management about the use of computers in business.

In 1958, he moved to White Plains, New York
White Plains, New York
White Plains is a city and the county seat of Westchester County, New York, United States. It is located in south-central Westchester, about east of the Hudson River and northwest of Long Island Sound...

 and continued working at IBM until his retirement in 1982.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK