Leonard nelson
Euclid
Hi, I am not an expert, but I could share some info about phenomenal mathematicians . I could define 3 of them:
1. Daniel Bernoulli (created the Bernoulli Principle underlying air flight and the concept that heat is merely molecules of random kinetic energy)
2. Alexis Claude Clairaut (contributed significantly to differential equations and mathematical physics and developed the idea of skew curves–the earliest precursors of spatial curvature)
3. Jean-Baptiste le Rond d’Alembert (invented some techniques that are currently applied in today’s physics, such as the method of eigenvalues used to solve the resultant linear systems and also the Cauchy-Riemann equations)
To find the name wouldn't it be required to know , which country the questioner is belong to ?
It's not easy to know who you mean by 'foreign' without knowing what your nationality is, since of course your definition of foreign depends on that. However, you may like to look at this list which claims to show the 30 greatest mathematicians of all time - they are a mixture of nationalities, so some of them are bound to be foreign to you!