English

The asymptotic number of equivalence classes of linear codes with given dimension

Information Theory 2025-10-17 v1 Combinatorics math.IT

Abstract

We investigate the asymptotic number of equivalence classes of linear codes with prescribed length and dimension. While the total number of inequivalent codes of a given length has been studied previously, the case where the dimension varies as a function of the length has not yet been considered. We derive explicit asymptotic formulas for the number of equivalence classes under three standard notions of equivalence, for a fixed alphabet size and increasing length. Our approach also yields an exact asymptotic expression for the sum of all q-binomial coefficients, which is of independent interest and answers an open question in this context. Finally, we establish a natural connection between these asymptotic quantities and certain discrete Gaussian distributions arising from Brownian motion, providing a probabilistic interpretation of our results.

Keywords

Cite

@article{arxiv.2510.14424,
  title  = {The asymptotic number of equivalence classes of linear codes with given dimension},
  author = {Andrea Di Giusto and Alberto Ravagnani},
  journal= {arXiv preprint arXiv:2510.14424},
  year   = {2025}
}