Odds and ends....and class records - Page 22

Dubslow · 2018-01-12, 21:19

That's not surprising or uncommon at all?

Batalov · 2018-03-15, 23:21

1033878

Code:

...
1884  140  1210024075...00<140> = 2^6 · 5^2 · 127 · 136765630999<12> · 263151616937453<15> · 9255912103178722959401214503081<31> · 1787590630...19<78>
1885  140  1790835631...00<140> = 2^6 · 5^2 · 127^2 · 6939501952...21<132>
1886  140  2650709943...98<140> = 2 · 127 · 1511 · 218422447 · 4466223823<10> · 6398431107...11<53> · 1106503459...37<64>

Dubslow · 2018-03-16, 00:21

Now that's pretty unlikely

what are the odds there? Perhaps 1/10^4, 1/10^5?

Batalov · 2018-08-30, 03:13

Eeek,,,
2005020 has length 15169.

EdH · 2018-08-30, 16:24

Quote:

Originally Posted by Batalov

Eeek,,,
2005020 has length 15070.

And most of those at <100 dd...

LaurV · 2018-09-21, 05:59

Some nice and (kind of) rare break of D3 on seq 181428, at index 1028 (close to 160 digits), without doubling of the 5 - but doubling the 3, and getting a lucky C154 cofactor which split in two primes, 41*P153, haha, both being 1 (mod 4), so we went from 2^3*3^2*5 to 2^4*3^2*5^2*11^2, then 11^3, then it lost the 5's and all the small primes except a 3. We are struggling now with the C156 (still in ecm phase).

LaurV · 2018-10-19, 03:44

Replying to myself again... it seems like nobody talks to me anymore

Mister 45792 (or is is Ms? Or Mrs, better!) gave use heart palpitations, when, after the Tibetan Plateau where it didn't want to raise and it didn't want to fall for what it seemed to us to be a million terms, we were expecting to see the Everest, but actually it got the DD and it went down...

Then, it lost the DD exactly at index 1400 (!) and it went through a lot of changes from 2^2 to 2^3 to 2^4, even tapped into 2^9, but then it ended up with 2^3*5 guide.

We said "well, that was it".

But it still surprised us, when it lost the guide after just 4 steps, in quite an unexpected way. We knew from the past that you can lose the G3 without squaring the 5 (see also my former post about losing D3 in a similar way) but we didn't see it yet, in our reservations, and it was a time when we worked a lot of D3 sequences just because they used to "scary" the people off.. (see our former discussions with Frank, when we joined the aliquot club here on this forum).

(by the way, where is Frank? He didn't post for ages, and we didn't see him around too much for more than 6 months, did he win his lottery and forgot about us?

)

Now, Mrs. 45792 has a 2^3 with no tail, and we really love this, almost as much as we love the DD. That is because this is like a "second DD", (like the "deputy sheriff" hehe). Because 2^3 with no tail of 3 or 5 can not get a 3 or a 5 attached to it, until it gets rid of the third power of 2. And because of that, 2^3 goes usually down, not as fast as the DD, but yet, we love it more than 2^2, for example (where 3 and 5 can come and go as they please).

It could be quite nice to see a 5-starter termination, we didn't see one in ages...

LaurV · 2018-10-22, 11:23

Let's bet if we get a symmetric graph...

Drdmitry · 2020-03-31, 01:20

As far as I can see, there are only four aliquot sequences below 1000000 which never reached 140 digits:
15390 (reserved by yafu@home, last update 31.03.2020),
62820 (Batalov, 27.03.2019),
780576 (Batalov, 11.03.2019),
407232 (johnadam74, 27.04.2019).

Among them, only the first one is actively developed. The other three were not continued for almost a year and look abandoned.

I think it would be great to reach a threshold of 140 digits for all sequences below 1e6. The last three sequences may either be unreserved, so someone else will be able to pick them up. Or Serge, you can continue with your two sequences till 140 digits. I suspect, that should not take too long.

yoyo · 2020-03-31, 17:59

I'll take the 3 to yafu@home to proceed them a bit, at least to a C139.

Drdmitry · 2020-06-12, 01:09

Finally, all aliquot sequences below 1e6 reach 140 digits at east once.

It looks like the next milestone of 150 digits will take very long time.

2018-09-21, 05:59	#237
LaurV Romulan Interpreter Jun 2011 Thailand 9369₁₀ Posts	For the 'happy me' thread... Some nice and (kind of) rare break of D3 on seq 181428, at index 1028 (close to 160 digits), without doubling of the 5 - but doubling the 3, and getting a lucky C154 cofactor which split in two primes, 41P153, haha, both being 1 (mod 4), so we went from 2^33^25 to 2^43^25^211^2, then 11^3, then it lost the 5's and all the small primes except a 3. We are struggling now with the C156 (still in ecm phase).

2018-10-19, 03:44	#238
LaurV Romulan Interpreter Jun 2011 Thailand 3³·347 Posts	Replying to myself again... it seems like nobody talks to me anymore Mister 45792 (or is is Ms? Or Mrs, better!) gave use heart palpitations, when, after the Tibetan Plateau where it didn't want to raise and it didn't want to fall for what it seemed to us to be a million terms, we were expecting to see the Everest, but actually it got the DD and it went down... Then, it lost the DD exactly at index 1400 (!) and it went through a lot of changes from 2^2 to 2^3 to 2^4, even tapped into 2^9, but then it ended up with 2^35 guide. We said "well, that was it". But it still surprised us, when it lost the guide after just 4 steps, in quite an unexpected way. We knew from the past that you can lose the G3 without squaring the 5 (see also my former post about losing D3 in a similar way) but we didn't see it yet, in our reservations, and it was a time when we worked a lot of D3 sequences just because they used to "scary" the people off.. (see our former discussions with Frank, when we joined the aliquot club here on this forum). (by the way, where is Frank? He didn't post for ages, and we didn't see him around too much for more than 6 months, did he win his lottery and forgot about us? ) Now, Mrs. 45792 has a 2^3 with no tail, and we really love this, almost as much as we love the DD. That is because this is like a "second DD", (like the "deputy sheriff" hehe). Because 2^3 with no tail of 3 or 5 can not get a 3 or a 5 attached to it, until it gets rid of the third power of 2. And because of that, 2^3 goes usually down, not as fast as the DD, but yet, we love it more than 2^2, for example (where 3 and 5 can come and go as they please). It could be quite nice to see a 5-starter termination, we didn't see one in ages... Last fiddled with by LaurV on 2018-10-19 at 03:50 Reason: spacing (we really hate this now!)*

2020-03-31, 01:20	#240
Drdmitry Nov 2011 2⁴·3·5 Posts	As far as I can see, there are only four aliquot sequences below 1000000 which never reached 140 digits: 15390 (reserved by yafu@home, last update 31.03.2020), 62820 (Batalov, 27.03.2019), 780576 (Batalov, 11.03.2019), 407232 (johnadam74, 27.04.2019). Among them, only the first one is actively developed. The other three were not continued for almost a year and look abandoned. I think it would be great to reach a threshold of 140 digits for all sequences below 1e6. The last three sequences may either be unreserved, so someone else will be able to pick them up. Or Serge, you can continue with your two sequences till 140 digits. I suspect, that should not take too long. Last fiddled with by Drdmitry on 2020-03-31 at 01:21

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2018-01-12, 21:19	#232
Dubslow Basketry That Evening! "Bunslow the Bold" Jun 2011 40<A<43 -89<O<-88 1110000110101₂ Posts	That's not surprising or uncommon at all?

2018-03-16, 00:21	#234
Dubslow Basketry That Evening! "Bunslow the Bold" Jun 2011 40<A<43 -89<O<-88 3·29·83 Posts	Now that's pretty unlikely what are the odds there? Perhaps 1/10^4, 1/10^5?

2018-08-30, 03:13	#235
Batalov "Serge" Mar 2008 Phi(4,2^7658614+1)/2 41×229 Posts	Eeek,,, 2005020 has length 15169.

2018-10-22, 11:23	#239
LaurV Romulan Interpreter Jun 2011 Thailand 3³·347 Posts	Let's bet if we get a symmetric graph...

2020-03-31, 17:59	#241
yoyo Oct 2006 Berlin, Germany 2²·3²·17 Posts	I'll take the 3 to yafu@home to proceed them a bit, at least to a C139.

2020-06-12, 01:09	#242
Drdmitry Nov 2011 2⁴·3·5 Posts	Finally, all aliquot sequences below 1e6 reach 140 digits at east once. It looks like the next milestone of 150 digits will take very long time.