John M. Pollard (born 1941) is a British

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

who has invented algorithms for the

factorization In mathematics, factorization (or factorisation, see English spelling differences) or factoring consists of writing a number or another mathematical object as a product of several ''factors'', usually smaller or simpler objects of the same kind ...

of large numbers and for the calculation of

discrete logarithm In mathematics, for given real numbers ''a'' and ''b'', the logarithm log''b'' ''a'' is a number ''x'' such that . Analogously, in any group ''G'', powers ''b'k'' can be defined for all integers ''k'', and the discrete logarithm log' ...

s. His factorization algorithms include the

rho Rho (uppercase Ρ, lowercase ρ or ; el, ρο or el, ρω, label=none) is the 17th letter of the Greek alphabet. In the system of Greek numerals it has a value of 100. It is derived from Phoenician letter res . Its uppercase form uses the sa ...

, ''p'' − 1, and the first version of the special number field sieve, which has since been improved by others. His discrete logarithm algorithms include the rho algorithm for logarithms and the kangaroo algorithm. He received the

RSA Award for Excellence in Mathematics RSA may refer to: Organizations Academia and education *Rabbinical Seminary of America, a yeshiva in New York City * Regional Science Association International (formerly the Regional Science Association), a US-based learned society * Renaissance ...

External links

John Pollard's web site
Living people 20th-century British mathematicians 21st-century British mathematicians Number theorists Place of birth missing (living people) 1941 births {{UK-mathematician-stub