# How can I number subtheorems hierachically?

I want to create two hierarchy levels of theorems. The goal is to have something like this:

Research Question 1: bla bla
Research Question 2: bla bla


And then in another section of the article, I would like to do something like this:

Research Question 1.1 bla bla
Research Question 1.2 bla bla

Research Question 2.1 bla bla
Research Question 2.2 bla bla


I used the following code:

\newtheorem{researchquestion}{Research Question}

\makeatletter
\newenvironment{subresearchquestion}[1]{%
\def\subtheoremcounter{#1}%
\refstepcounter{#1}%
\protected@edef\theparentnumber{\csname the#1\endcsname}%
\setcounter{parentnumber}{\value{#1}}%
\setcounter{#1}{0}%
\expandafter\def\csname the#1\endcsname{\theparentnumber.\Alph{#1}}%
\ignorespaces
}{%
\setcounter{\subtheoremcounter}{\value{parentnumber}}%
\ignorespacesafterend
}
\makeatother
\newcounter{parentnumber}


However, the result is not exactly how it should look like: Research Question 1: bla bla Research Question 2: bla bla

And then in another section of the article, I would like to do something like this:

Research Question 3.1 bla bla
Research Question 3.2 bla bla

Research Question 4.1 bla bla
Research Question 4.2 bla bla


How can I achieve that the subtheorems are really subtheorems? I tried this approach: How to number subtheorems hierarchically? but the problem then is that the theorem numbering is influenced by the section numbering. I want this two things have independently.

• It's not really clear: the questions you number 1.1 and 1.2 should refer to the question numbered 1, while 3.1 has nothing to do with a question 3? Feb 13, 2014 at 15:27

\documentclass{article}

\newtheorem{theorem}{Theorem}[section]
\newtheorem{subtheorem}{Sub-Theorem}[theorem]

\renewcommand{\thetheorem}{\arabic{theorem}}
\renewcommand{\thesubtheorem}{\arabic{theorem}.\arabic{subtheorem}}

\begin{document}
\section{Introduction}

\begin{theorem}
\end{theorem}

\begin{subtheorem}
\end{subtheorem}

\begin{subtheorem}
\end{subtheorem}

\begin{theorem}