Yes, I know... I should have offered 4 p: 1 2 3 4x or something similar. Cheers,
Mike Sent from my iPad > On 25 Apr 2020, at 13:20, Henry Rich <[email protected]> wrote: > > 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 >>> >> > > > -- > This email has been checked for viruses by AVG. > https://www.avg.com > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
