X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Flibrary%2Fnat%2Fsigma_and_pi.ma;h=84301b49adf80d9aeab35c83b405bf8b50dc71f7;hb=7f82161596bdfccc1179f5edcc0bfd76d34516b5;hp=fe3a2d8b5d417502ac99e5572a1a759a7e448bba;hpb=3889d8624f9589749cf5b3ce4297db0f1a557779;p=helm.git

diff --git a/matita/library/nat/sigma_and_pi.ma b/matita/library/nat/sigma_and_pi.ma
index fe3a2d8b5..84301b49a 100644
--- a/matita/library/nat/sigma_and_pi.ma
+++ b/matita/library/nat/sigma_and_pi.ma
@@ -16,6 +16,7 @@ set "baseuri" "cic:/matita/nat/sigma_and_pi".
 
 include "nat/factorial.ma".
 include "nat/exp.ma".
+include "nat/lt_arith.ma".
 
 let rec sigma n f m \def
   match n with