Einar Steingrímsson (born 20 July 1955) is an Icelandic mathematician whose research lies in

enumerative combinatorics Enumerative combinatorics is an area of combinatorics that deals with the number of ways that certain patterns can be formed. Two examples of this type of problem are counting combinations and counting permutations. More generally, given an inf ...

, especially the study of

permutation pattern In combinatorial mathematics and theoretical computer science, a (classical) permutation pattern is a sub-permutation of a longer permutation. Any permutation may be written in one-line notation as a sequence of entries representing the result of a ...

s and

permutation statistics The statistics of random permutations, such as the cycle structure of a random permutation are of fundamental importance in the analysis of algorithms, especially of sorting algorithms, which operate on random permutations. Suppose, for example, t ...

. He is a research professor (emeritus) in the School of Mathematics and Statistics at the

University of Strathclyde The University of Strathclyde () is a public research university located in Glasgow, Scotland. Founded in 1796 as the Andersonian Institute, it is Glasgow's second-oldest university, having received its royal charter in 1964 as the first techn ...

Early life and education

Einar grew up in Reykjavík and left secondary school early at age eighteen (the normal graduation age at the time was twenty), and trained as a ship builder at Slippstöðin in

Akureyri Akureyri (, ) is a town in northern Iceland, the country's fifth most populous Municipalities of Iceland, municipality (under the official name of Akureyrarbær , 'town of Akureyri') and the largest outside the Capital Region (Iceland), Capital R ...

. After completing qualifying examinations independently, he enrolled at the

University of Pennsylvania The University of Pennsylvania (Penn or UPenn) is a Private university, private Ivy League research university in Philadelphia, Pennsylvania, United States. One of nine colonial colleges, it was chartered in 1755 through the efforts of f ...

. He graduated there as a BA and MA in mathematics in 1987, and as PhD at the

Massachusetts Institute of Technology The Massachusetts Institute of Technology (MIT) is a Private university, private research university in Cambridge, Massachusetts, United States. Established in 1861, MIT has played a significant role in the development of many areas of moder ...

in 1992 under the supervision of Richard P. Stanley; his dissertation was titled ''Permutation Statistics of Indexed and Poset Permutations''.

Career

Einar moved to

Gothenburg Gothenburg ( ; ) is the List of urban areas in Sweden by population, second-largest city in Sweden, after the capital Stockholm, and the fifth-largest in the Nordic countries. Situated by the Kattegat on the west coast of Sweden, it is the gub ...

, Sweden in 1990, while still a graduate student at the Massachusetts Institute of Technology, and in 1992, Einar was hired at

Chalmers University of Technology Chalmers University of Technology (, commonly referred to as Chalmers) is a private university, private research university located in Gothenburg, Sweden. Chalmers focuses on engineering and science, but more broadly it also conducts research ...

as part of the joint mathematics institute with the

University of Gothenburg The University of Gothenburg () is a List of universities in Sweden, university in Sweden's second largest city, Gothenburg. Founded in 1891, the university is the third-oldest of the current List of universities in Sweden#Public universities, S ...

. In 2004 he became a professor of mathematics at Reykjavik University. From 2010 to 2021 he was a professor at the

in Glasgow, Scotland.

Research

Einar's research focuses on permutation statistics, pattern avoidance, and related enumerative problems. * In a 1994 paper he studied permutation statistics defined on colored permutations (then called indexed permutations), relating them to classical statistics such as descents and inversions. * In a 2000 paper joint with Eric Babson, he introduced vincular permutation patterns (then called "generalized patterns"); that paper also classified Mahonian statistics expressible via these patterns. * New Euler–Mahonian bi-statistics on permutations and words were described in a joint work with R. J. Clarke and Jiang Zeng, extending earlier Eulerian–Mahonian results. * Connections between permutation tableaux and pattern avoidance were examined in his joint work with Lauren K. Williams, linking tableaux combinatorics to steady-state distributions in the asymmetric simple exclusion process. * His joint work with Anders Claesson and Vít Jelínek established that the growth rate of the class of 1324-avoiding permutations is at most 16, and presented a still-open conjecture that if true would lower this bound to

e^

, approximately 13.00195.

References

External links

Personal homepage
{{DEFAULTSORT:Steingrimsson, Einar 1955 births Living people People from Reykjavík Icelandic mathematicians Combinatorialists