Lol. This root is double-counted. 1 1 1 1 358358 /Erling
On 2017-11-03 16:42, Erling Hellenäs wrote:
Hi all!
My take:
v=:1 1 1 1 2 7 11 13 179
r=:5 parRuskeyE 9
r2=: >r (*/)@:{&.>"1 0 < v
r3=:/:~"1 r2
r4=: ~.r3
NB. One root is 1 1 1 1 358358
NB. All permutations
(!5)*1+#r4
6360
Cheers,
Erling Hellenäs
On 2017-11-03 15:03, Erling Hellenäs wrote:
Sorry. Add ones. /Erling
On 2017-11-03 15:00, Erling Hellenäs wrote:
OK. The five prime factors are needed if you want to multiply 5
numbers and get 358358, except that you can possibly add zeros and
358358 itself? /Erling
On 2017-11-03 14:35, 'Mike Day' via Programming wrote:
Language differences?
Personally, I tend to be rather careless, using the terms
“factor” and “divisor” for the same thing, when “divisor” is
perhaps to be preferred. However, Pari GP provides a library
function “factor” to deliver the prime factorisation of its
argument, in a similar fashion to J’s q: .
So, strictly speaking, perhaps, the factors of 358358 are 2 7 11
13 179 and its divisors are 1 2 7 11 13 14 22 etc...
You’re both right!
Mike
Please reply to [email protected].
Sent from my iPad
On 3 Nov 2017, at 11:25, Erling Hellenäs
<[email protected]> wrote:
Hi all!
Raul:
"Hmm... actually, thinking about it, the par approach here is not
efficient enough for this example. 5 parRuskeyE 32 is too big of a
result, I think. (358358 has 5 distinct prime factors and, thus, 32
integer factors.)"
However there are only 5 integer factors:
q: 358358
2 7 11 13 179
*/q:358358
358358
Now you ask me for 44 5 integer factorizations.
As far as I understand there is only one 5 integer factorization
of 358358 unless you count 1 and 358358 as factors.
In any case it can be handled by parRuskeyE.
Cheers,
Erling Hellenäs
Den 2017-11-03 kl. 10:58, skrev Raul Miller:
I'm not sure where you showed the 44 different 5 integer
factorizations of 358358?
Thanks,
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