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Old 2019-12-26, 06:28   #34
ldesnogu
 
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Quote:
Originally Posted by storm5510 View Post
I have found "an" instance of 1,432. I had to start at 1e51 to do it. Are there instances of this gap in lower primes? I would say yes.
The smallest known starts at 84218359021503505748941. See https://faculty.lynchburg.edu/~nicel...html#MainTable
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Old 2019-12-27, 03:36   #35
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Quote:
Originally Posted by ldesnogu View Post
The smallest known starts at 84218359021503505748941. See https://faculty.lynchburg.edu/~nicel...html#MainTable
Thank you. I suspected there would be a gap of the same size at a lower number.
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Old 2019-12-30, 16:26   #36
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Quote:
Originally Posted by ldesnogu View Post
The smallest known starts at 84218359021503505748941. See https://faculty.lynchburg.edu/~nicel...html#MainTable
This project may be dead. I sent an email asking a question and it was blocked. I found the content extremely interesting though.

Edit: His website does not respond either.

Last fiddled with by storm5510 on 2019-12-30 at 16:30 Reason: Additional
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Old 2019-12-30, 16:53   #37
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It is a copy of the website of Thomas R. Nicely (http://trnicely.net/) who passed away 3.5 months ago, see here:
https://mersenneforum.org/showthread.php?t=24904
and here:
https://mersenneforum.org/showthread.php?t=22641
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Old 2019-12-31, 00:05   #38
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Quote:
Originally Posted by ATH View Post
It is a copy of the website of Thomas R. Nicely (http://trnicely.net/) who passed away 3.5 months ago, see here:
https://mersenneforum.org/showthread.php?t=24904
and here:
https://mersenneforum.org/showthread.php?t=22641
Oh my! Now I feel like an idiot for for writing of it the way I did.

It appears his work continues in the second link. The output format is different. What was this ran with, if I may ask?
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Old 2020-01-07, 23:35   #39
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Just as an experiment, I tried searching for gaps of 1,000 and higher. I did 817-million comparisons and only found 40. Sample:

Code:
1000  173562042121603559000003155443277
1002  173562042121603559000009313185819
1004  173562042121603559000002684964513
1006  173562042121603559000012622835333
1006  173562042121603559000021527745167
1010  173562042121603559000000189000813
1012  173562042121603559000006819710501
1014  173562042121603559000001570624289
1016  173562042121603559000003875758521
1018  173562042121603559000005211487823
1020  173562042121603559000001398445077
1022  173562042121603559000002896404777
1024  173562042121603559000009761558327
1026  173562042121603559000003582270737
1028  173562042121603559000025383168849
1030  173562042121603559000006243898871
1032  173562042121603559000001018813277
1034  173562042121603559000003529371099
1036  173562042121603559000011033798393
The largest I found was 1444. This process is very time consuming. My hat is off to anyone having the patience to search for these.
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Old 2020-01-10, 16:13   #40
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For about the last five days, I have been working on a Strawberry Perl script to search for prime gaps. With a little advice from robert44444uk, it is a working script.

It reads what it is supposed to run from a file I call work.txt. This contains a single line consisting of three numbers separated by commas: start, stop, filter. Example: 1048573, 2200000,100. In this case, anything >= 100 is printed on the screen and written into a file I call results.txt. I could not think of a better name. The work.txt file is updated every 15 seconds by using a timer routine. This may seem too frequent to some. I set it to this because the script covers a lot of territory rapidly. Pressing Ctrl-C stops the script and saves its current values into the work file. There is a simple capture for this to redirect it to a sub.

Each output line contains an initiating prime, an end prime, and the gap between in CSV format. I am going to cut this back to the initiating prime and the gap because the output file grows rather rapidly. This is capable of handling very large numbers, as in the attachment below. This short test started at 1e59 which is 60 digits.

I compiled the script into a Windows executable program. The first compile was 12 MB. By removing some unused modules, I got this down to 8 MB. I feel this is rather large coming from a script containing 64 lines, including white-space. I will try to improve on this by doing more web research. I need to add some traps to catch any irregularities in the work file also.

I know many here use Linux. After I have done what I feel is enough testing, and have made the needed changes, I will make the script available here.The only change I see is the modification of the environment line at the top. Mine is "#1 C:\Strawberry." Linux would be something like "#! /usr/bin/env perl." Anyone having a Linux install of Strawberry should not have any problems running this script. Other variations would probably require some code changes.

A week ago, I knew nothing about Perl. My long programming background made this far easier to learn. I have often asked myself why I should try to learn something like this when I am 64 years old. I guess the proper answer would be that it is never too late to learn something new. I have enjoyed the process greatly. I do the best I can.
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Old 2020-01-29, 22:52   #41
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You can find prime gap lists on OEIS.
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