--- /dev/null
+include "basics/logic.ma".
+
+\ 5img class="anchor" src="icons/tick.png" id="N"\ 6axiom N : Type[0].
+\ 5img class="anchor" src="icons/tick.png" id="add"\ 6axiom add : \ 5a href="cic:/matita/cicm2012/naturals/N.dec"\ 6N\ 5/a\ 6 → \ 5a href="cic:/matita/cicm2012/naturals/N.dec"\ 6N\ 5/a\ 6 → \ 5a href="cic:/matita/cicm2012/naturals/N.dec"\ 6N\ 5/a\ 6.
+\ 5img class="anchor" src="icons/tick.png" id="times"\ 6axiom times : \ 5a href="cic:/matita/cicm2012/naturals/N.dec"\ 6N\ 5/a\ 6 → \ 5a href="cic:/matita/cicm2012/naturals/N.dec"\ 6N\ 5/a\ 6 → \ 5a href="cic:/matita/cicm2012/naturals/N.dec"\ 6N\ 5/a\ 6.