In the autumn of the same year, Wiman went to Lund University studying Mathematics, Botany and Latin.

In a paper for approximations to small denominators in 1900, Wiman applied measure theory to the probabilistic problem, and became the first person to do so.

In 1901, Wiman accepted an extraordinary professorship in algebra and number theory at Uppsala University.

[3] Wiman wrote the article on finite groups of linear transformations for Klein's encyclopedia.

[7][8] Wiman's theorems for quasiregular mappings shows that an entire holomorphic function of order less than 1/2 has a minimum modulus converging to along a sequence.

[1] His investigations on the zeros of the derivatives of entire functions — along with similar investigations by George Pólya – had a great influence on the theory of entire functions; in particular, the now-proved Wiman conjecture,[10] [11] and the now-proved Pólya-Wiman conjecture[12] have inspired much research.