It's a pretty good improvement already.
hc10k =: , ] +/@:{~ (,&<: -.)@{:
AnN =: % 1+i.@:# NB. a(n)/n
MxAnN =: >./;.1~ 2 (=<.)@:^. 1...@# NB. Max a(n)/n btw successive 2^
HCF=. 3 : '1 1,(#2...@#);(,<@;@(|.@(#;. 1) (],~1$~[)&.>
<@:>:;.1)@>@{:)^:(y-2) <2'
6!:2 'xx=. mx...@ann 1 1 hc10k @]^:[~ 2^20'
2485.4382
6!:2 'xx2=. mx...@ann HCF 20'
0.38284575
xx-:xx2
0
>./|xx-xx2
9.536725e_7
(] i. >./) |xx-xx2
20
20{&>xx;xx2
0.50000095 0.5
I notice the non-J examples on Rosetta Code have full-blown examples of
output; perhaps the J example could end with a line like:
>(<'Maximum of "a(n)/n" >=2^'),&.>(":&.>i.#xx2),&.>(<' and
<2^'),&.>(":&.>>:i.#xx2),&.>(<' is '),&.>":&.>xx2
Maximum of "a(n)/n" >:2^0 and <2^1 is 1
Maximum of "a(n)/n" >:2^1 and <2^2 is 0.66666667
Maximum of "a(n)/n" >:2^2 and <2^3 is 0.66666667
Maximum of "a(n)/n" >:2^3 and <2^4 is 0.63636364
...
On Thu, Mar 11, 2010 at 12:37 PM, Aai <[email protected]> wrote:
> Still working on it. Perhaps it's possible to improve this approach :-)
>
> ...
--
Devon McCormick, CFA
^me^ at acm.
org is my
preferred e-mail
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