I am a professor in the Math Department of the University of the Basque Country. I got my PhD at Washington University in St. Louis. My research interests are PDE's and Number Theory. My hobbies are sailing and travelling around the word.
19 Inverse of a bijection f is equal to its derivative jan 15 '13
18 Can any two irrational numbers NOT of the form (m+A) and (n-A) be added to produce a rational number? sep 19
16 If $p$ is prime, does there exist a positive integer $k$ such that $2^k\,p+1$ is also prime? jun 3 '12
15 Is there a non-decreasing sequence $(a_n)$ such that $\sum 1/a_n=\infty$ and $\sum1/(n+a_n)<\infty$? nov 21 '11
13 The number is a perfect square if and only if $k=n$ jul 17 '11