Reserved for MF - Sequence 4788 - Page 234

henryzz · 2016-09-11, 18:44

Quote:

Originally Posted by VBCurtis

Why not edit it now? I vote for a temporary ban if he continues to use white text. Not acceptable.

Mainly because I was busy. Handing my dissertation in tomorrow. I may got back and edit that one when I have time.

henryzz · 2016-09-11, 19:27

Quote:

Originally Posted by mshelikoff

I'm still writing about this topic after I wrote "nevermind," so I apologize for writing "nevermind" because obviously I'm still thinking about it, and I'm fairly new to the forum and might be making a mistake by asking this question now. But...

What are the odds of this sequence meeting itself and creating a very large cycle if the sequence dips below a given number of digits (I'll use 7) and then terminates? Maybe it's an unlikely precondition before even considering the chances of the event if the precondition takes place. But I'm curious about it and wondering if I'm thinking about it the right way. I'm not talking about when a merger is found but how the final sequence at factordb will appear.

If the count of non-untouchable numbers above 10^7 with an immediate descendant below 10^7 were used as a denominator and the count of the subset of those numbers that belong to the 4788 genealogy were used as the numerator, would that fraction give a reasonable estimate of the odds?

I'm using the word "odds" as if this were a horse race instead of the given fixed probabilities in Raman's post, but that seems to be part of the appeal of following these things.

I think that this is an incredibly hard question to answer. I think that each number has a different number of numbers that can precede it. This implies to me that it is not a simple formula as 4788 has a certain subset of the numbers below 10^7. I think that working this out would be exceedingly difficult.
Working out all the numbers that can precede a number in a sequence is not easy.

ATH · 2016-09-11, 19:58

In step 6295 it reached:
108779027694592579666495916767464 (33 digits)

and then it went up again. Now it is back to 88 digits in step 6666.

ryanp · 2016-09-11, 20:08

And now we're going down again, as of terms 6700 onward...

firejuggler · 2016-09-11, 20:24

got down as low s 18 digits, now it went up to 70 digits

science_man_88 · 2016-09-11, 20:25

Quote:

Originally Posted by firejuggler

i 7200-7300 it's hovering around 20-25 digits

and at 7581 it's back up to over 60. edit: and moving so fast I can't keep this up to date 7639 and 71 digits now edit2: changed already.

unconnected · 2016-09-11, 20:26

Minimum at 16 digits and now it grows with 2^2*7 driver.

mshelikoff · 2016-09-11, 20:30

It looks like it picked up a 2^2·7 at the 16 digit 1987170707261684 , found the downdriver later, and then picked up another 2^2·7 at 20 digits and this one isn't leaving.

firejuggler · 2016-09-11, 20:30

This is almost heartbreaking.

Batalov · 2016-09-11, 21:27

Just as heartbreaking as the previous bottom.
But then again look at AllSeq page - there are constantly 30-40 downdrivers but only 1 per few months terminations/merges...

Not all is lost just yet!

ATH · 2016-09-11, 21:37

Minimum was step 7189:
1987170707261684 (16 digits)

2016-09-11, 20:24	#2568
firejuggler Apr 2010 Over the rainbow 2³×5²×13 Posts	got down as low s 18 digits, now it went up to 70 digits Last fiddled with by firejuggler on 2016-09-11 at 20:26

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Reserved for MF - Sequence 3366	RichD	Aliquot Sequences	470	2021-04-22 02:17
Reserved for MF - Sequence 3408	RichD	Aliquot Sequences	474	2021-03-07 20:28
Reserved for MF - Sequence 276	kar_bon	Aliquot Sequences	127	2020-12-17 10:05
Assignments are reserved but not showing up	prism019	GPU to 72	6	2020-09-21 22:11
80M to 64 bits ... but not really reserved	petrw1	Lone Mersenne Hunters	82	2010-01-11 01:57

2016-09-11, 19:58	#2566
ATH Einyen Dec 2003 Denmark 3⁵·13 Posts	In step 6295 it reached: 108779027694592579666495916767464 (33 digits) and then it went up again. Now it is back to 88 digits in step 6666.

2016-09-11, 20:08	#2567
ryanp Jun 2012 Boulder, CO 17² Posts	And now we're going down again, as of terms 6700 onward...

2016-09-11, 20:26	#2570
unconnected May 2009 Russia, Moscow 13·199 Posts	Minimum at 16 digits and now it grows with 2^2*7 driver.

2016-09-11, 20:30	#2571
mshelikoff "Marc Shelikoff" Dec 2014 Cambridge, MA 1111₂ Posts	It looks like it picked up a 2^2·7 at the 16 digit 1987170707261684 , found the downdriver later, and then picked up another 2^2·7 at 20 digits and this one isn't leaving.

2016-09-11, 20:30	#2572
firejuggler Apr 2010 Over the rainbow 2³·5²·13 Posts	This is almost heartbreaking.

2016-09-11, 21:27	#2573
Batalov "Serge" Mar 2008 Phi(4,2^7658614+1)/2 2×7×677 Posts	Just as heartbreaking as the previous bottom. But then again look at AllSeq page - there are constantly 30-40 downdrivers but only 1 per few months terminations/merges... Not all is lost just yet!

2016-09-11, 21:37	#2574
ATH Einyen Dec 2003 Denmark 3⁵·13 Posts	Minimum was step 7189: 1987170707261684 (16 digits)