progs/mkphrase.c: Fix trailing spaces in usage message.

[catacomb] / math / strongprime.h

diff --git a/math/strongprime.h b/math/strongprime.h
index 9010236..14ad39e 100644 (file)
--- a/math/strongprime.h
+++ b/math/strongprime.h
@@ -60,7 +60,14 @@
  * Use:                Sets up for a strong prime search, so that primes with
  *             particular properties can be found.  It's probably important
  *             to note that the number left in the filter context @f@ is
- *             congruent to 2 (mod 4).
+ *             congruent to 2 (mod 4); that the jump value is twice the
+ *             product of two large primes; and that the starting point is
+ *             at least %$3 \cdot 2^{N-2}$%.  (Hence, if you multiply two
+ *             such numbers, the product is at least
+ *
+ *                     %$9 \cdot 2^{2N-4} > 2^{2N-1}$%
+ *
+ *             i.e., it will be (at least) a %$2 N$%-bit value.
  */
 
 extern mp *strongprime_setup(const char */*name*/, mp */*d*/, pfilt */*f*/,