Anonymous user
Talk:Untouchable numbers: Difference between revisions
m
→reduction in the number of (counting) ranges: check if limit*factor with factor = limit^(1/3)
m (→reduction in the number of (counting) ranges: check if limit*factor with factor = limit^(1/3)) |
|||
Line 17:
I've reduced the number of ranges for counting untouchable numbers. It seems the upper limit for searching for touchable numbers was far higher than I guesstimated. -- [[User:Gerard Schildberger|Gerard Schildberger]] ([[User talk:Gerard Schildberger|talk]]) 09:28, 9 February 2021 (UTC)
:I have checked counting ranges, but, as Nigel stated , that's not the way to get an reliable result, when changing the upper limit.
<pre>
Limit //100*1000*1000;//10*1000*1000;//5*1000*1000;//1000*1000;
factor //384( to small ) ;//152;//104;//64; // search area = factor*Limit</pre>
:How about using Goldbach conjectue ( tested true > 1e18 ).All numbers a sum of max three primes<BR>
proper div sum(p*q) = 1+p+q / p<>q and both prime and p*q <Limit
proper div sum(p*q*r) = 1+p+q+r+p*q+p*r+q*r/ p<>q<>r and all prime and p*q*r <Limit
: is limit for checks == limit^(1/3)
: I'll test it with 1e8 and factor 464 will take ~30min
== Number of untouchable numbers up to 1 million ==
| |||