renamed "rulify" to "rulified";
renamed "less_induct" to "nat_less_induct";
(*<*)theory fakenat = Main:;(*>*)text{*\noindentThe type \isaindexbold{nat}\index{*0|bold}\index{*Suc|bold} of naturalnumbers is predefined and behaves like*}datatype nat = 0 | Suc nat(*<*)end(*>*)