diff --git a/buddy/ChangeLog b/buddy/ChangeLog
index eacb95c01..90e5a8cf9 100644
--- a/buddy/ChangeLog
+++ b/buddy/ChangeLog
@@ -1,3 +1,8 @@
+2011-11-12  Alexandre Duret-Lutz  <adl@lrde.epita.fr>
+
+	* src/kernel.h (PAIR, TRIPLE): Redefine these hash functions using
+	something that is simpler to compute.
+
 2011-08-28  Alexandre Duret-Lutz  <adl@lrde.epita.fr>
 
 	* examples/adder/adder.cxx (test_vector): Add parentheses to
diff --git a/buddy/src/kernel.h b/buddy/src/kernel.h
index 05cb98c13..8138a7534 100644
--- a/buddy/src/kernel.h
+++ b/buddy/src/kernel.h
@@ -153,9 +153,8 @@ extern bddCacheStat bddcachestats;
 
    /* Hashfunctions */
 
-#define PAIR(a,b)      ((unsigned int)((((unsigned int)a)+((unsigned int)b))*(((unsigned int)a)+((unsigned int)b)+((unsigned int)1))/((unsigned int)2)+((unsigned int)a)))
-#define TRIPLE(a,b,c)  ((unsigned int)(PAIR((unsigned int)c,PAIR(a,b))))
-
+#define PAIR(a,b)     (((unsigned)a)+((unsigned)b)*12582917U)
+#define TRIPLE(a,b,c) (((unsigned)a)+((unsigned)b)*12582917U+((unsigned)c)*4256249U)
 
    /* Inspection of BDD nodes */
 #define ISCONST(a) ((a) < 2)