### My Erdös number is 3 (see also zbMATH).

This number is used in mathematics to show that mathematics is a strongly
interlinked science.
Build a graph where each mathematician is a vertex and a connection edge
between two vertices indicates that these two mathematics have published a
joint paper. Then, the Erdös number of a given mathematician
is the minimal number of edges (=joint papers) you need to reach Erdös from
that person.
Erdös was a famous mathematician with about 1000 publications and around
100 different coauthors (the ones with Erdös number 1)

**0. Paul Erdös**

Paul Erdös & David Preiss:
Decomposition of spheres in Hilbert spaces.
Comment. Math. Univ. Carolinae 17 (1976), no. 4, 791--795.

**1. David Preiss**

David Preiss & Vladimír Sverák: Derivatives of type $1$.
Real Anal. Exchange 12 (1986/87) 354--360.

**2. Vladimír Sverák**

Vladimír Sverák & Tomás Roubíček:
Nonexistence of solutions in nonconvex multidimensional variational problems.
J. Convex Anal. 7 (2000) 427--435.

**3. Tomáš Roubíček**

.