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-   -   Archived reservation posts (https://www.mersenneforum.org/showthread.php?t=14330)

Batalov 2010-02-08 20:29

Reserving 898224: i2055 . c81 [COLOR=blue]2^4*3[/COLOR]
Releasing 851730: i1784 . c120 [COLOR=darkred]2^2*7[/COLOR]

10metreh 2010-02-08 20:33

[QUOTE=henryzz;204939]Does 748356 have a driver with
[COLOR=Black]2^3 * 3^2 * 5 or not?
I seem to remember someone saying that [/COLOR][COLOR=Black]2^3 * 3^2 * 5 can't go down to [/COLOR][COLOR=Black]2^3 * 3 * 5 but even if that is impossible then surely the sequence has the driver 2^3 * 3[/COLOR][/QUOTE]

I count 2^3 * 3^2 * 5 as a driver because it can drop back to the ordinary 3^1 when the 5 is squared. However, 2^5 * 3^2 * 7 can't, so that is a guide.

Greebley 2010-02-09 15:34

I personally like thinking of it as a guide because it is easier to escape than for a driver and is unlikely to drop to a single 3 (in which case it would now be a driver). This differs from other square terms which are easier to lose the square (2^2*7^2 for example will often lose the square).

Alternatively, I calculated that the chance of 2^3*3^2*5 escaping is around 1/41 at 100 digits. Just decide if that is 'good enough' for you to run it.

Note that if the 5 is also square you can pick up the down driver.

Incidentally, 2^3*3 is also easier to escape than any other driver and is about the same chance as 2^3*3^2*5 - around 1/40. If one defined a driver based on the chance of escape, I don't think either of these would qualify for drivers.

henryzz 2010-02-09 17:17

reserving
[URL="http://factordb.com/search.php?se=1&aq=803064&action=last20&fr=&to="]803064[/URL]
[URL="http://factordb.com/search.php?se=1&aq=803928&action=last20&fr=&to="]803928[/URL]
unreserving
157752
235416
236754

schickel 2010-02-12 10:03

Reserving 20916 (target 120+ or escape from [COLOR="Red"]2^6 * 127[/COLOR]...)

Batalov 2010-02-14 21:02

Reserving 850956 at i288.

henryzz 2010-02-15 17:18

unreserving 232680

henryzz 2010-02-15 17:36

reserving 807612

Batalov 2010-02-22 02:00

1 Attachment(s)
Keeping 821232 reserved from the subproject.
It's been a fun sequence so far:

biwema 2010-02-22 21:27

Reserving 794880 (again)

I did quite a bit work on that sequence, but reporting is impossible because it is broken on the database (and cannot be repaired).

I will keep it for the time being to prevent other people doing duplicate work.

It is possible to delete the last few indexes?
So i could submit the corrected version then.

Batalov 2010-02-26 03:49

Reserving 836976 at i485.


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