Talk:N-smooth numbers: Difference between revisions
→there are no 9-smooth numbers?: new section
(→Disagreement among implementations: fixed the REXX problem.) |
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: The output of REXX for the optional sub-task is indeed incorrect, as some of the values are not really p-smooth. One such example is 38123 = 67 * 569. -- [[User:Trizen|Trizen]] ([[User talk:Trizen|talk]]) 09:34, 29 August 2019 (UTC)
:: I found the problem. Once the problem was found, it was so obvious. I don't want to go into the embarrassing details too much, but some of the simplest errors are so easy to overlook. What triggered the ''ah-ha!'' moment was the last line of the 1<sup>st</sup> batch of output, the 10<sup>th</sup> prime (and all others above that) were indexed incorrectly, the program has an internal table of the first nine primes, all higher primes are generated. Pesky little bug, ... the primes were being generated correctly, but their ''indices'' were incorrect, which manifested itself only when indices for primes > 23 were being used. But many thanks for noticing the problem in the output(s). I'm now glad that I put the (high) requirement in. Without those ginormous numbers, the error might not have been detected. Also, I had
:: It was a fun project, albeit that I spent way too many an hour on it. Not to mention all the coal I had to shovel to keep the steam-driven ole computer running. -- [[User:Gerard Schildberger|Gerard Schildberger]] ([[User talk:Gerard Schildberger|talk]]) 13:12, 29 August 2019 (UTC)
:::FWIW: Right now the REXX example is showing different outputs for the same inputs (See inputs for sub task 2 & 3) Obviously the ''code'' is working correctly, it looks like may be a copy/paste error. --[[User:Thundergnat|Thundergnat]] ([[User talk:Thundergnat|talk]]) 11:33, 30 August 2019 (UTC)
:::: (To quote Charlie Brown) Arrrrgh! I'll get it right, eventually. ... Fixed. -- [[User:Gerard Schildberger|Gerard Schildberger]] ([[User talk:Gerard Schildberger|talk]]) 18:30, 30 August 2019 (UTC)
== there are no 9-smooth numbers? ==
From the task description, second sentence:
<blockquote>The n (when using it in the expression n-smooth is always prime, there are no 9-smooth numbers.</blockquote>
I don't know, [[wp:Smooth_number#Definition|Wikipedia: Smooth number]] in the Definition section, paragraph 3, sentence 3 seems to directly contradict that.
<blockquote>Usually B is prime, but composite numbers are permitted as well.</blockquote>
Ok, they use B rather than N but there isn't anything special about B; that is just the indeterminate they used. (Also, that sentence seems to be missing a closing parenthesis.) --[[User:Thundergnat|Thundergnat]] ([[User talk:Thundergnat|talk]]) 22:15, 31 October 2019 (UTC)
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