[QUOTE=Mr. P-1;328963]Lucky in what sense? Lucky that there was a P43 waiting to be found? That depends upon how much ECM other people had done before me.[/QUOTE]
You have a very nice find, but I don't think it is that rare. For example, I found a 42-digit factor of the c198 of [URL="http://www.factordb.com/index.php?id=1000000000012151257"]2^1233+1[/URL] on January 2, this year, with B1=3000000. While I can't be certain I was the first to find it, it wasn't in factordb. [There is still a c157, and I have done "just enough" ECM that it's a statistical tie whether ECM or GNFS is more efficient to finish it. (I moved the c157 to my GNFS queue, but it will be months before I get to it, if ever. I do not claim any sort of "reservation" on this number.)]

As you say, it all depends how much ECM other people have done before us. Once you get above the Cunningham Table limits (including proposed extensions), there seem to be a lot of numbers that haven't been worked extensively.

[QUOTE=rcv;328990]While I can't be certain I was the first to find it, it wasn't in factordb.[/QUOTE]

Obviously I can't be certain about mine either, but I'd checked [url=http://www.garlic.com/~wedgingt/mersenne.html]Edgington's database[/url] as well as factordb. Unfortunately I'd missed [url=http://homes.cerias.purdue.edu/~ssw/cun/xtend/other]this[/url] and [url=http://homes.cerias.purdue.edu/~ssw/cun/xtend/crombie]this[/url]. Fortunately my find wasn't on either list. It's there now.

new factor found
 

First time I ever messed with GPU/mfaktc, (my) first factor..beginner's luck...

M83833487 has a factor: 318129387684576210031 (68.1 bits)
k=3×5×23×431×12760271

M60809621 has a factor: 2905866497364711208590790240514270083169
131.09 Bits; k = 23893147577459093262485472821104 = 2 * 2 * 2 * 2 * 271 * 1451 * 3037 * 13441 * 210601 * 329209 * 1341863

Slightly below my personal record, I guess it is my 2nd largest so far.

P-1 found a factor in stage #1, B1=580000.
UID: Jwb52z/Clay, M61705447 has a factor: 2614309415709170708616361

81.113 bits.

My first P-1 success with my new box:

[code][Thu Feb 21 23:47:32 2013]
P-1 found a factor in stage #2, B1=585000, B2=11992500, E=6.
UID: daran/agogo, M61797409 has a factor: 13497681001092947908111, AID: 8941DF002A23E43404FBEEE76A6CA876[/code]

74 bits (previously TFed to 73). k=3*5*109*27827*800117.

P-1 factor for [COLOR=black]59,750,861[/COLOR], [URL="http://www.mersenne.ca/factor/87542740676833513855994017"]87542740676833513855994017[/URL] 86 bits.

Nuts. My first P-1 factor after rejoining the effort was a paltry 74.09 bits. The only reason it even merits a post is the ridiculously tiny/smooth k: [URL="http://www.mersenne.ca/exponent.php?exponentdetails=59898271"]min B2 is only 4751[/URL].

Looks like you got something a [strike]LOT[/strike] bit better!

77.8 bits for you! :razz:

[COLOR=Silver]Hmm, also it looks like [strike]I found[/strike] minion No. 7 found a P-1 factor just now, [SIZE=2]542430480860023763539783 for [/SIZE][/COLOR][SIZE=2][COLOR=Silver]59928367[/COLOR][SIZE=2][COLOR=Silver], 78 bits.[/COLOR]
[/SIZE][/SIZE]

Actually, that computer got very lucky overnight, but still paltry factors of 74.2 and 77.9 (again) bits. The 597049xx range has been quite lucrative for P-1 factors.

Edit: It seems kracker just got another hit of his own, also above 78 bits :razz:

[code]kracker ccc-node-07 59928367 F-PM1 2013-02-25 20:09 0.0 542430480860023763539783[/code]

P-1 found a factor in stage #2, B1=580000, B2=10730000.
UID: Jwb52z/Clay, M61769167 has a factor: 3552790399080178821438689

81.555 bits.