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Old 2018-04-29, 19:55   #1
sweety439
 
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Default OEIS sequence A088782

This sequence is in fact the reversed Sierpinski problem with k=10, according to the thread http://mersenneforum.org/showthread.php?t=10354&page=8, this sequence can be extended to a(184), and a(185) is > 10^6 due to the Sierpinski base 185 problem, and the related sequence A088783 can be added another term 177, since a prime 10*173^264234 is known.

Also the sequence A119624 (the reversed Sierpinski problem with k=2) can be extended to a(364), and A119591 (the reversed Riesel problem with k=2) can be extended to a(580).
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Old 2018-04-30, 06:43   #2
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You are absolutely right. This is about primes 10*b^t + 1 for fixed b when t runs from 1 through infinity. You call it reversed Sierpiński?

I am extending A088783 as you suggested (see "History" of the entry until edits are approved).

/JeppeSN
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Old 2018-04-30, 14:05   #3
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Quote:
Originally Posted by JeppeSN View Post
You are absolutely right. This is about primes 10*b^t + 1 for fixed b when t runs from 1 through infinity. You call it reversed Sierpiński?

I am extending A088783 as you suggested (see "History" of the entry until edits are approved).

/JeppeSN
Not just I called, please see A263500.

You can also extend A088782 to n=184, A119624 to n=364, A253178 to n=242 and A119591 to n=580 (by create a b-file).

Last fiddled with by sweety439 on 2018-04-30 at 14:05
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Old 2018-04-30, 14:09   #4
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Besides, you can create a-files for these sequences for the status (with some unknown terms, you can use "?" for them and give the test limits) to n=1000.
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Old 2018-04-30, 15:21   #5
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OK, it is a reference to Krywaruczenko, Daniel (2008) "A Reverse Sierpinski Number Problem," Rose-Hulman Undergraduate Mathematics Journal: Vol. 9 : Iss. 2 , Article 4. I will fix the link to that paper in OEIS. /JeppeSN
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Old 2018-04-30, 19:16   #6
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Quote:
Originally Posted by sweety439 View Post
Besides, you can create a-files for these sequences for the status (with some unknown terms, you can use "?" for them and give the test limits) to n=1000.
Also write a reference to CRUS page.
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Old 2018-04-30, 19:17   #7
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Originally Posted by JeppeSN View Post
For A263500, I found a(n) for all n<=64 in the post http://mersenneforum.org/showpost.ph...56&postcount=2.
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Old 2018-04-30, 22:52   #8
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Sweety439, I think you should update those OEIS entries yourself. /JeppeSN
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