1) P+1 factoring. A worktodo.txt entry looks like this:
Pplus1=k,b,n,c,B1,B2,nth_run[,how_far_factored][,"known_factors"]
Unlike P-1, the fact that factors of Mersenne numbers is 1 mod 2p is of no value.
Thus, P-1 is vastly more effective at finding factors. A P+1 run is about as
valuable as running one ECM curve. P+1 stage 1 is 50% slower than P-1 stage 1
but several times faster than ECM stage 1. P+1 stage 2 is a little faster than
P-1 stage 2 which in turn is a little faster than ECM stage 2.
Unlike P-1, P+1 has only a 50% chance of finding a factor if factor+1 is B1/B2 smooth.
Thus, it makes sense to do 1 or 2 (maybe 3) runs. That is what the nth_run argument is for.
There are two special starting values for P+1 that have a slightly higher chance of
finding a factor. These special starting values correspond to nth_run=1 and nth_run=2.
Like P-1, if how_far_factored is specified, prime95 will ignore B2 and calculate the
best B2 value for the given B1.
2) Faster ECM stage 1 when factoring exponents near the limit of an FFT size.
3) Gwnum library new functions give a programmer more tools to reduce normalized adds.
A tutorial.txt file is now available to help a programmer use the gwnum library.
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