factor: fix comments
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/coreutils/factor.c b/coreutils/factor.c
index 8ca3de7..4e521db 100644
--- a/coreutils/factor.c
+++ b/coreutils/factor.c
@@ -54,7 +54,7 @@
// if (N == 0)
// return 0;
- /* First approximation x > sqrt(N) - half as many bits:
+ /* First approximation of x+1 > sqrt(N) - all-ones, half as many bits:
* 1xxxxx -> 111 (six bits to three)
* 01xxxx -> 111
* 001xxx -> 011
@@ -125,7 +125,7 @@
if (factor >= max_factor)
break;
factor += 2;
- /* Rudimentary wheel sieving: skip multiples of 3:
+ /* Rudimentary wheel sieving: skip multiples of 3, 5 and 7:
* Every third odd number is divisible by three and thus isn't a prime:
* 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47...
* ^ ^ ^ ^ ^ ^ ^ _ ^ ^ _ ^ ^ ^ ^