X-Git-Url: https://git.distorted.org.uk/~mdw/catacomb/blobdiff_plain/0f00dc4c8eb47e67bc0f148c2dd109f73a451e0a..HEAD:/math/pgen.h

diff --git a/math/pgen.h b/math/pgen.h
index b103c30e..eef91414 100644
--- a/math/pgen.h
+++ b/math/pgen.h
@@ -270,6 +270,29 @@ extern mp *pgen(const char */*name*/, mp */*d*/, mp */*m*/,
 		unsigned /*steps*/, pgen_proc */*step*/, void */*sctx*/,
 		unsigned /*tests*/, pgen_proc */*test*/, void */*tctx*/);
 
+/* --- @pgen_granfrob@ --- *
+ *
+ * Arguments:	@mp *n@ = an integer to test
+ *		@int a, b@ = coefficients; if @a@ is zero then choose
+ *			automatically
+ *
+ * Returns:	One of the @PGEN_...@ codes.
+ *
+ * Use:		Performs a quadratic version of Grantham's Frobenius
+ *		primality test, which is a simple extension of the standard
+ *		Lucas test.
+ *
+ *		If %$a^2 - 4 b$% is a perfect square then the test can't
+ *		work; this function returns @PGEN_ABORT@ under these
+ *		circumstances.
+ *
+ *		If @a@ is zero on entry, then the function will choose
+ *		suitable parameters deterministically -- i.e., it always
+ *		chooses the same parameters for a given %$n$%.
+ */
+
+extern int pgen_granfrob(mp */*n*/, int /*a*/, int /*b*/);
+
 /* --- @pgen_primep@ --- *
  *
  * Arguments:	@mp *p@ = a number to check