About Riho Terras
Lived 1939 – 2005 (aged 66). Riho Terras was an Estonian and American mathematician.
Riho Terras (June 13, 1939 – November 28, 2005) was an Estonian-American mathematician. He was born in Tartu, Estonia, and moved to Ulm, Germany, before starting school. In 1951, he emigrated to the United States along with his mother. He finished his PhD in 1970 at the University of Illinois Urbana-Champaign.
He is known for the Terras theorem about the Collatz conjecture, published in 1976, which proved that the conjecture holds for "almost all" numbers and established bounds for the conjecture.
He married fellow mathematician Audrey Terras.
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Important facts
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Frequently asked questions
Who was Riho Terras?
Estonian-American mathematician (1939–2005)
When was Riho Terras born?
Riho Terras was born on 13 June 1939 in Tartu.
When did Riho Terras die?
Riho Terras died on 28 November 2005 in San Diego.
What was Riho Terras's occupation?
Riho Terras was a mathematician.
What nationality was Riho Terras?
Riho Terras was Estonian and American.
Sources & further reading
· DBpedia: Riho Terras (mathematician)
Cite this page
APA: Biography.guide. (2026). Riho Terras. https://biography.guide/riho-terras/
MLA: "Riho Terras." Biography.guide, https://biography.guide/riho-terras/.
Chicago: "Riho Terras." Biography.guide. https://biography.guide/riho-terras/.
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