I don't even know how to start this question. I have problem. I declared `\newtheorem{twi}[5.1.]{}` and it won't compile + start making theory counter from **5.1.**, **5.2.** etc... :/ I'm new in LaTeX and I use it just because university... so... for me it's useless but I need to end what I have started.

Example of how I want to use it:

```
\documentclass[leqno]{article}
\usepackage{amssymb, amsmath}
\newtheorem{twi}[5.1.]{}
\begin{document}
\begin{twi}
Something here
\end{twi}
\begin{twi}
Something here again
\end{twi}
\end{document}

```

and I want output like

> 
> 5.1. Something here
> 
> 
> 5.2. Something here again
> 
> 
> 

---

Ok, thanks to all of you I found motivation to make it and search for my own solution.