The bug seems to be confined to the argument 1x . 4 p: x searches x+2,
x+4, ... for primes. It starts at x+1 if x is even or is non-extended
1; but for extended 1 it starts at x+2.
Henry Rich
On 4/25/2020 4:48 AM, 'Michael Day' via Programming wrote:
Investigating how to factor quite large numbers in J, I've just
bumped into this curiosity, which
wrecked my loopy experiment at an early stage!...
4 p: 1
2
4 p: 1x NB. need to try extended in some cases...
3
!
Thanks for any advice,
Mike
On 25/04/2020 00:15, 'Mike Day' via Programming wrote:
Numbers of divisors below, not the divisors themselves... the thread
had split! I was attempting to comment on Hauke Rehr’s post.
M
Sent from my iPad
On 24 Apr 2020, at 23:52, 'Jon' via Programming
<[email protected]> wrote:
This is missing a few divisors. It seems Skip's original method
would be difficult to beat. It's O(n) in time and space. You could
improve space complexity by doing a simple loop, but as far as I can
see there are no shortcuts, and the best way is to just "brute
force" it.
Sent from BlueMail
On Apr 25, 2020, 5:35 AM, at 5:35 AM, 'Mike Day' via Programming
<[email protected]> wrote:
I think this is near to the approved way:
(*/"1@:>:@(_& q:))24 360 4711
8 24 4
Mike
Sent from my iPad
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