Henry Howland Crapo (KRAYpoh;^{[1]} August 12, 1932 – September 3, 2019) was an AmericanCanadian mathematician who worked in algebraic combinatorics. Over the course of his career, he held positions at several universities and research institutes in Canada and France. He is noted for his work in matroid theory and lattice theory.
Henry Crapo  

Pronunciation 

Born  Henry Howland Crapo August 12, 1932 
Died  September 3, 2019  (aged 87)
Citizenship  American, Canadian 
Alma mater  Massachusetts Institute of Technology (Ph.D.) 
Known for  Matroid theory 
Scientific career  
Fields  Mathematics 
Thesis  On the Theory of Combinatorial Independence (1964) 
Doctoral advisors  GianCarlo Rota, Kenneth Hoffman 
Crapo was born in Detroit, Michigan, in 1932.^{[2]}^{[3]} He received his Ph.D. in 1964 under the supervision of GianCarlo Rota and Kenneth Hoffman, with thesis On the theory of combinatorial independence.^{[4]}^{[5]} While working on his thesis, he was an Assistant Professor at Northeastern University in Boston.^{[5]}^{[6]} He subsequently held academic positions at the University of Waterloo, Université de Montréal, INRIA Rocquencourt, and École des Hautes Études en Sciences Sociales.^{[7]} During his time in Waterloo, Crapo became a Canadian citizen.^{[3]}
Crapo is known for his early work in matroid theory, and for related work in lattice theory. He introduced the beta invariant of a matroid,^{[8]} and published the first paper on the Tutte polynomial^{[9]} (though Tutte had already defined an equivalent polynomial in his thesis). Together with GianCarlo Rota, Crapo wrote the first book on matroid theory.^{[10]}^{[11]} He is also known for Crapo's Complementation Theorem in poset Möbius Inversion.^{[12]}^{[13]} Crapo wrote 65 mathematical publications during his career.^{[14]}
Upon his retirement, Crapo moved to the south of France.^{[3]} He continued some mathematical activity, and hosted several small conferences at his house there.^{[11]} He died on September 3, 2019.^{[15]}
Crapo was a patron of the arts. At the University of Waterloo he donated a collection of rare books on the history of dance and ballet,^{[17]} as well as a copy of the Porcellino sculpture of Florence; the latter shoulderhigh bronze sculpture of a wild boar later became a mascot for the University of Waterloo Faculty of Arts.^{[18]} He also donated The Temptation of St. Anthony by James Ensor to the Royal Museum of Fine Arts in Antwerp^{[3]} and Corpse of Man by Hyman Bloom to the Rose Art Museum at Brandeis University.^{[19]}