Talk:Parasitic number
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Currently, this article only really talks about the smallest n-parasitic numbers, and doesn't talk about parasitic numbers in a base other than base 10. Anyone who could expand in these directions, please do so. Mangojuicetalk 14:25, 17 May 2006 (UTC)
[edit] Merged content per AfD
I've merged content from 105263157894736842 (number) per AfD, but since I don't usually edit mathematics-related articles on a regular basis, I hope someone who does can edit my additions appropriately. --Deathphoenix ʕ 14:51, 23 May 2006 (UTC)
- When I created this article, I merged everything I could, so I undid what you added (but it's in the history if anyone wants to see). The fact that (that number) is the decimal expansion of 1/19, and what parasitic numbers are, is covered already, and there wasn't anything else to merge. Mangojuicetalk 15:09, 23 May 2006 (UTC)
- Thanks. Hmmm... I could be mistaken, but one of the actions we strongly suggest against taking on an article during an AfD (in the AfD guide) is to merge content because of potential problems with GFDL if the consensus is to delete the article in question. Still, the article was kept as a merge & redirect, so no harm done. :-) --Deathphoenix ʕ 14:02, 24 May 2006 (UTC)
- Perhaps it would have been better if the article had been moved, and then edited to the first version I made? Mangojuicetalk 15:00, 25 May 2006 (UTC)
- Perhaps. It doesn't matter now because the redirect is in place. You can make it a cut and paste of whatever version is in the original article's history now. --Deathphoenix ʕ 15:13, 25 May 2006 (UTC)
- Perhaps it would have been better if the article had been moved, and then edited to the first version I made? Mangojuicetalk 15:00, 25 May 2006 (UTC)
- Thanks. Hmmm... I could be mistaken, but one of the actions we strongly suggest against taking on an article during an AfD (in the AfD guide) is to merge content because of potential problems with GFDL if the consensus is to delete the article in question. Still, the article was kept as a merge & redirect, so no harm done. :-) --Deathphoenix ʕ 14:02, 24 May 2006 (UTC)
[edit] n = 5
I'm afraid the smallest 5-parasitic number really is 142857, rather than the 1020408163265030612244897959183673469387755 originally calculated. I need to work on the formula to absorb that information. — Arthur Rubin | (talk) 13:06, 9 June 2006 (UTC)
This is fascinating, actually. 5 is the only exception, I'm pretty sure. It seems to me the interesting thing about the case of n=5 is that 49 is square, unlike several of the other values (such as 19 and 29) which are prime. More importantly, the repeating decimal part of 1/7 is only 6 digits long, whereas the repeating decimal part of 1/49 is much longer. I don't think there's an exception for n=4; 39 isn't prime, but 1/39 has just as long a pattern as 1/13, and 1/3 is obviously not so useful here. 59 is also prime. 69 = 3*23, but again 1/23 has just as long a pattern as 1/69, and 1/3 won't work because we'll always get extra digits, not a rotation. 79 and 89 are also prime, so no issue there. In order to have a lower period, the parasitic number would need to be based on a fraction with a shorter period, and only a divisor of (10n-1) would make that happen. Mangojuicetalk 20:22, 9 June 2006 (UTC)
