Ivan Niven

Ivan Morton Niven (October 25, 1915 – May 9, 1999) was a Canadian-American mathematician, specializing in number theory. He was born in Vancouver. He did his undergraduate studies at the University of British Columbia and was awarded his doctorate in 1938 from the University of Chicago. He was a member of the University of Oregon faculty from 1947 to his retirement in 1981. He received the University of Oregon's Charles E. Johnson Award in 1981.

Niven completed the solution of most of Waring's problem in 1944. This problem, based on a 1770 conjecture by Edward Waring, consists of finding the smallest number ${\displaystyle g(n)}$ such that every positive integer is the sum of at most ${\displaystyle g(n)}$ ${\displaystyle n}$th powers of positive integers. David Hilbert had proved the existence of such a ${\displaystyle g(n)}$ in 1909; Niven's work established the value of ${\displaystyle g(n)}$ for all but finitely many values of ${\displaystyle n}$.

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