Template:Fibonacci序列
{{subst:Xn+1,Xn.a}}{{subst:!}}{{subst:#expr:{{{2}}}}}+{{subst:#expr:{{{1}}}}}{{subst:!}}{{{1}}}{{subst:Xn+1,Xn.c}}
{{subst:Xn+1,Xn.a}}{{subst:!}}{{subst:#expr:{{{2}}}}}+{{subst:#expr:{{{1}}}}}{{subst:!}}{{{1}}}{{subst:Xn+1,Xn.c}}