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Talk:Taxicab numbers: Difference between revisions
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In http://mathworld.wolfram.com/TaxicabNumber.html it says a Taxicab number has to be defined n ways, not just 2 ways. So at minimum, this may be a bad title. --[[User:TimToady|TimToady]] ([[User talk:TimToady|talk]]) 05:45, 14 March 2014 (UTC)
: Yes, I'm aware that Wolfram's MathWorld (TM) defines taxicab numbers differently than OEIS does (well, only in part). OEIS also used this alternative definition as A11541. OEIS entry A1235 is the one that is used for a model: ''Taxi-cab numbers: sums of 2 cubes in more than 1 way''. I specifically noted that this (more or less) is the definition used here in this task. If OEIS defines it thusly, I saw no reason not to use that name
:: P.S. I don't mind someone changing my quotes/wording (in the talk sections) if there is are typos, misspellings, or bad or outdated links, but not the wording or the look-and-form. After all, the good Samaritan thing is to make the original intent clear and not obfuscated with my bad spelling and/or typos. I was given the impression that my "talk-section" words aren't to be (or shouldn't be) edited and/or reformatted, or in someone's words, inviolate, immutable. I would put things like italicizing, bold facing (it that a word?), superscripting/subscripting and the like into this category. I have corrected misspellings in the past, but have been told that those changes were possible inappropriate. I prefer that my paragraphs have sentences with a double blank after each sentence, and other stuff such as keywords, keyphrases, mathematical notations, and such thingys for readability --- unless you think that ''' ''' has some other meaning or use. I hate to revert changes to other people's changes to my wording (either in content or form). I assume the intent of the changes is to make my words easier to read, but it's my choice to have more blanks to make the words, phrases, mathematical expressions, or sentences easier to peruse. Removing them from my wording doesn't do so in my opinion, and I'd like the intent of my words or phrasing to remain unaltered. A couple of blanks hither and thither shouldn't be a bother. -- [[User:Gerard Schildberger|Gerard Schildberger]] ([[User talk:Gerard Schildberger|talk]]) 20:46, 14 March 2014 (UTC)
==Extra credit discrepancy==
'''Extra credit answers of Python and Rexx do not agree'''. If you swap the commented <code>sumcubes</code> line in and use it instead of the line above in the Python solution I can derive exactly the same Python result by explicitly counting the ''sets'' of different ways forming the sums of two cubes. --[[User:Paddy3118|Paddy3118]] ([[User talk:Paddy3118|talk]]) 08:42, 14 March 2014 (UTC)
: I don't quite fully understand what you just wrote (two things). Did you say if you swap a Python statement around, it produces the same result as the REXX extra-credit solution? The other thing I don't understand is what ''sets'' Python is counting (''sets'' of two sums of cubes?). Are you saying something about '''1+3''' is the same ''set'' as '''3+1'''? Since the REXX solution has lower numbers than the Python solution (in the 2,000 range extra-credit thingy), I suspect one reason may be that the REXX version is computing more taxicab numbers, and since they are out of order, the more taxicab numbers are generated, the more likely chance that a lower taxicab number would be found. One method of resolving this would be for me to (re-)generate the list, but this time, list all 2,007 numbers (and look for mirror sums. There shouldn't be any, but I've been wrong before (once or twice ...). By the way, a nit ... The Python is one number short.
The OEIS A001235 b-file gives the extra credit answers as
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:This still leaves a problem with REXX which doesn't agree with the b-file at oeis.org/A001235/b001235.txt, for example REXX 2000'th == b-file 2080'th value. --[[User:Paddy3118|Paddy3118]] ([[User talk:Paddy3118|talk]]) 17:40, 14 March 2014 (UTC)
:: This'll take some time, so please be patient if I don't get back within a couple of days. What I really need is another fast PeeCee and a clone or two to work on this stuff. -- [[User:Gerard Schildberger|Gerard Schildberger]] ([[User talk:Gerard Schildberger|talk]]) 20:46, 14 March 2014 (UTC)
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