diff --git a/data/qp2.png b/data/qp2.png
index 55dac420..a81e611e 100644
Binary files a/data/qp2.png and b/data/qp2.png differ
diff --git a/data/qp2_hd.png b/data/qp2_hd.png
new file mode 100644
index 00000000..55dac420
Binary files /dev/null and b/data/qp2_hd.png differ
diff --git a/ocaml/Makefile b/ocaml/Makefile
index aaf8c2cc..6ff91273 100644
--- a/ocaml/Makefile
+++ b/ocaml/Makefile
@@ -43,7 +43,7 @@ $(QP_ROOT)/data/executables: remake_executables element_create_db.byte Qptypes.m
 	$(QP_ROOT)/ocaml/element_create_db.byte
 
 external_libs:
-	opam install cryptokit core
+	opam install cryptokit sexplib
 
 qpackage.odocl: $(MLIFILES)
 	ls $(MLIFILES) | sed "s/\.mli//" > qpackage.odocl
diff --git a/ocaml/qptypes_generator.ml b/ocaml/qptypes_generator.ml
index 353c91c4..a63a19cc 100644
--- a/ocaml/qptypes_generator.ml
+++ b/ocaml/qptypes_generator.ml
@@ -58,7 +58,7 @@ let input_data = "
 
 * Det_number_max : int
   assert (x > 0) ;
-  if (x > 50_00_000_000) then
+  if (x > 50_000_000_000) then
     warning \"More than 50 billion determinants\";
 
 * States_number : int