Yes, it is. Please ZIP it if you can. Or ARC it, or ....Is it okay to send a couple of hundred Kb to your e-mail add.?

I don't know what my ISP's limit is, but we'll find out. Perhaps, you could break it up into convenient "Chunks".

As far as the iterations go, I'm using the following table:

The following table gives a set of near-to-optimal B1 and B2 pairs, with the corresponding expected number of curves to find a factor of given size (this table does not take into account the "extra factors" found by Brent-Suyama's extension, see

below).

digits D optimal B1 B2 expected curves N(B1,B2,D)

15 2e3 1.2e5 30

20 11e3 1.4e6 90

25 5e4 1.2e7 240

30 25e4 1.1e8 500

35 1e6 8.4e8 1100

40 3e6 4.0e9 2900

45 11e6 2.6e10 5500

50 43e6 1.8e11 9000

55 11e7 6.8e11 22000

60 26e7 2.3e12 52000

65 85e7 1.3e13 83000

70 29e8 7.2e13 120000

Table 1: optimal B1 and expected number of curves to find a

factor of D digits.

Important note: the expected number of curves is significantly smaller than the "classical" one we get with B2=100*B1. This is due to the fact that this new version of gmp-ecm uses a default B2 which is much larger than 100*B1 (for large B1), thanks to the improvements in step 2.