Talk:Zumkeller numbers: Difference between revisions

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corrected some typos.
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m (corrected some typos.)
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if (n % 2 || d.size() >= 24)
return true;</pre>
99504 has 30 divisors and is not a zumkellerZumkeller number.<BR>
TestetTested with GO version:
<lang go>func main() {
fmt.Println("The first 220 Zumkeller numbers are:")
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99500 99504 99510 99512 99516 </pre>
 
Checked the first 100,000 zumkellerZumkeller numbers.<BR>
First occurenceoccurrence of Non-Zumkeller number with count of divisors
<pre>
Div
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I took a look and I'm not getting those numbers in the output. Can I see how you unit tested this? I'm not sure why that would matter though... my best guess is an OS dtype issue causing overflow but that seems unlikely. What IDE/OS did you run this on?--[[User:Mckann|Mckann]] ([[User talk:Mckann|talk]]) 03:35, 12 May 2021 (UTC)
: I think the overflow will happen with 32 Bit aka uint.<br>If you change d.size to >30-Bit it will take a while and find 99504 to be a non-zumkellerZumkeller number.<lang c++>// if we get here and n is odd it's a zum!
if (n % 2 || d.size() > 30)
return true;</lang>
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:: There is no.<BR>In '[[oeis:A083207|OEIS:A083207 - Zumkeller numbers]] someone stated and checked <pre>All 205283 odd abundant numbers less than 10^8 that have even abundance are Zumkeller numbers. - T. D. Noe, Nov 14 2010</pre> something one can use.
 
Oh I see. It works, empirically, for N >> max zumkellerZumkeller number needed for the problem and reduces runtime appreciably. That's the justification. I should put a comment in there, thank you. --[[User:Mckann|Mckann]] ([[User talk:Mckann|talk]]) 16:45, 15 May 2021 (UTC)
 
== Where to find count of zumkellerZumkeller to verify solutions.Is there a constant ratio 0.228...? ==
 
I have modified the program to run up to 1E9
<pre>Count of zumkellerZumkeller numbers up to 1,000,000,000
count n
224 1000 time 0.004 s