diff --git a/library/bignum.c b/library/bignum.c
index e7b8d6d..80cf0f8 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -530,7 +530,7 @@
             {
                 c = ( X->p[i - 1] >> ( ( j - 1 ) << 3) ) & 0xFF;
 
-                if( c == 0 && k == 0 && ( i + j + 3 ) != 0 )
+                if( c == 0 && k == 0 && ( i + j ) != 2 )
                     continue;
 
                 *(p++) = "0123456789ABCDEF" [c / 16];