Template:Rule 30 long/generate

{{subst:subst}}#ifexpr:{{{n}}}>0 |{{subst:subst}}Rule 30 long/generate {{subst:pipe}}n={{subst:#expr:{{{n}}}-1}} {{subst:rightbraces}}}}{{subst:lefttriplebraces}}{{{n}}}{{subst:righttriplebraces}}

Substituting this template produces one or more new substitution template calls, allowing recursive change of a page, see m:Help:Recursive conversion of wikitext.