The composite cofactor of 3,607- was the product of 85-digit, 96-digit, and 110-digit prime numbers:

85-digit prime factor:
2086414114912368934845698889752452759455632789377648284275990116236503745140234728069

96-digit prime factor:
120463408255967053578135908158245347326036064518355187873832329408825869652943374488400197042063

110-digit prime factor:
81529721835493524725988100443970680738653595633187211135428836315200448881013673156176891838179958882238447519

This is a new Cunningham project second-place SNFS record for size of the number factored. The factors will be reported to the Cunningham project and will be recorded on Page 119.

Is this number be factored use degree 6, I notice the poly of 6,379+ is
n: 190869828061621461659863636707439059948042541397156797021935219218350398154483149591895053229379732129532332295828579589760877766171097533506965397824066533846000077988917965921258973321630437676677267014005259227990906727916564002361612266675089370791738705252309553229
type: snfs
skew: 1
c6: 6
c5: 0
c4: 0
c3: 0
c2: 0
c1: 0
c0: 1
Y1: 1
Y0: -10556714443828879617693714491135314434982743638016
alim: 250000000
rlim: 200000000
lpbr: 33
lpba: 33
mfba: 66
mfbr: 96
alambda: 2.6
rlambda: 3.6

that is a degree 6,

but I read a article which suggest using degree 7 for SNFS 280 to 350.
So what's the matter here?

Simulations of the entire sieving range yield more relations for a degree 6 polynomial than for a degree 7, even for an upcoming 310 digit number.

Is this number be factored use degree 6, ...

but I read a article which suggest using degree 7 for SNFS 280 to 350.
So what's the matter here?

I'm somewhat curious as to which article you were reading; you're
most likely careful about sources, but the phrase "I read it on the
internet" (which you didn't use, I know) is often followed by info
that's not very reliable.

Another possible issue is that the 16e siever we're currently using
has some improvements (and/or corrections) in the assembly code due
to our friend Batalov. The initial source code of Franke/Kleinjung
is not very portable, and notoriously intricate, so that even a usually
reliable author may not have had the best code to work with. Establishing
a well docummented public source of data is one of the points of this
boinc project. There are very few public SNFS factorizations above
difficulty 280; and the author is quite likely making use of relatively
limited simulations, rather than examining the "entire sieving range yield".

-bdodson

OK, Here is a somewhat more detail information.
I fogot this article's title,
but it is indeed a journal article.
The author only discuss monic polynomial,
I can not understand the theory discussed in this article.
In fact I want to study polynomial selection or some other technique of factoring in my master degree,
but my tutor does not think I have the ability to do it, so I select another area in mathematics.

This article is published in a Chinese jornal, I'll find its title and journal later. After Greg deny the result, I almost forgot this thread.

I also curious about the slow progress in the study of nfs.
I find some articles in the past 3 years, but most of them are introduction,
a paper discussed multiple polynomial, and another paper discuss gnfs polynomial degree, but stopped at 6, but it does not discuss degree 7, I dont know why the max degree discussed is 6.

And Comparing with so many numbers have been factored in the past 5 years, the progress in factoring theory is slow, it is a little strange. RSA768 is degree 6, M1061 is degree 6, so if we want to factor RSA1024 ,or F12, is it possible to try to use degree 7.

Here is the article title and the journal name.

Zhang Peng, and Li Chao, "POLYNOMIAL SELECTIONS IN FACTORING r^e+-s WITH NFS",
Computer Applications and Software, no. 4, Vol. 26, pp. 28-30, Apr. 2009.

Zhang Peng is a postgraduate student in
Department of Mathematics and System Science, National University of Defense Technology, Changsha 410073, China.

This article's main conclusion is,
when N is less than 40 digits, degree should be 3;
when N's digit is between 40 to 100, should degree 4;
100 to 160, be degree 5;
170 to 270, be degree 6;
280 to 350, be degree 7.