20200826, 08:20  #507  
Oct 2011
2^{2}×5×19 Posts 
Quote:
OK, thanks a lot ! At the next update, I will reserve the base 12 for you. No, you don't take too much ! It all depends on YAFU's computing means. YAFU's statistics are very high at the moment. I don't know if a team is raiding on YAFU and if the statistics will stay so high in the next few times ? 

20200826, 08:48  #508  
Oct 2011
2^{2}·5·19 Posts 
Quote:
Ok, this time the file is perfect ! Thanks a lot Ed. I examined it closely. Unfortunately, nothing special catches my attention at the moment. Except a detail for the prime number 53 : there are only sequences that start on powers of 2 that end with the prime number 53. But this must be pure chance ! But maybe someone else will observe something interesting... 

20200826, 09:46  #509 
Oct 2011
101111100_{2} Posts 
I would also like to make a comment about a private conversation that Edwin Hall and I had in early July. Edwin allowed me to talk about this private conversation here when the messages are readable by everyone.
Here is Edwin's observation : Code:
Sequences that had abundant indices somewhere and a parity change other than at index 1 (all were due to perfect squares): (2^9, 2^62, 2^210): 81 >> 40 (2^12, 2^141, 2^278, 2^387): 49 >> 8 (2^112): 2209 >> 48 (2^117): 25921 >> 5600 (2^141): (729 >> 364) and (49 >> 8) (2^243): 1225 >> 542 (2^271): 2025 >> 1726 (2^305, 2^317): 9 >> 4 (2^421): 169 >> 14 Of the even numbers that were due to parity flips, only 40, 48, 364 and 5600, are abundant. I think we can generalize this study by looking at the table called "base_2_mat" that I attached to post #447. Here is an excerpt from this table : Code:
prime 2 in sequence 2^1 at index 0 prime 2 in sequence 2^2 at index 0 prime 2 in sequence 2^3 at index 0 prime 2 in sequence 2^4 at index 0 3 ... prime 2 in sequence 2^9 at index 0 3 4 prime 2 in sequence 2^10 at index 0 5 ... prime 2 in sequence 2^12 at index 0 8 ... prime 2 in sequence 2^14 at index 0 7 8 prime 2 in sequence 2^15 at index 0 7 8 ... prime 2 in sequence 2^55 at index 0 14 ... prime 2 in sequence 2^59 at index 0 12 13 ... prime 2 in sequence 2^62 at index 0 26 27 ... prime 2 in sequence 2^112 at index 0 62 63 64 ... prime 2 in sequence 2^117 at index 0 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 ... prime 2 in sequence 2^141 at index 0 25 26 27 28 34 ... prime 2 in sequence 2^164 at index 0 42 ... prime 2 in sequence 2^210 at index 0 44 45 46 49 50 ... prime 2 in sequence 2^243 at index 0 128 129 130 131 ... prime 2 in sequence 2^271 at index 0 79 80 81 82 83 84 85 86 87 88 89 ... prime 2 in sequence 2^278 at index 0 51 ... prime 2 in sequence 2^305 at index 0 76 ... prime 2 in sequence 2^317 at index 0 70 ... prime 2 in sequence 2^373 at index 0 94 95 96 97 ... prime 2 in sequence 2^387 at index 0 102 ... prime 2 in sequence 2^421 at index 0 65 66 67 ... prime 2 in sequence 2^510 at index 0 125 126 ... Unfortunately, here again: I don't notice anything about the exponents, nor the indexes that could allow to predict for which base 2 exponents, we have parts of sequences with the prime number 2 elsewhere than at the index 0 !!! 
20200826, 13:05  #510 
Sep 2008
Kansas
2^{2}×811 Posts 
I'll start work on Table n=29.

20200826, 13:37  #511 
Sep 2008
Kansas
CAC_{16} Posts 
Tabe n=29
This may be of interest because it flips parity.
http://factordb.com/sequences.php?se...ge&fr=32&to=42 
20200826, 13:37  #512 
Jun 2013
2·3·13 Posts 
Reserving 2310^25

20200826, 15:47  #513 
Oct 2011
101111100_{2} Posts 
@RichD :
OK for base 29. OK for 265^2, thank you very much ! This number was already in my tables... @Sergiosi : I think you have already finished the calculations for 2310^25. And moreover, it is a nontrivial end, which is rare ! Thanks a lot ! 
20200827, 20:40  #514 
Sep 2008
Kansas
110010101100_{2} Posts 
Who has the way back merge detection meter? I believe 20^37 has merged.

20200827, 21:27  #515 
"Ed Hall"
Dec 2009
Adirondack Mtns
110111011010_{2} Posts 

20200827, 22:37  #516 
"Rich"
Aug 2002
Benicia, California
10010101000_{2} Posts 

20200828, 01:14  #517 
Sep 2008
Kansas
2^{2}·811 Posts 
19^14 might have also merged.

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