[VA] Short & Sweet Math Challenge #24: "2019 Spring Special 5-tier"

[Valentin Albillo]

 
Hi J-F, long time no see !

(03-22-2019 08:04 AM)J-F Garnier Wrote:  (I noticed that the SSMC24 was Valentin's post #314 at the time of writing :-)

Yes, that was intentional on my part. Notice also that Paul Dale's post just before yours is his post #1444, i.e. 38², which has the maximum number of 4's (three) in which a square can end.

Quote:The problem implicitly assumes that the cin(x) function is unique, otherwise it would make no sense to discuss the cin(x) values. If we understand 'function' in the mathematic sense of an analytical, non-pathologic function, this may be true.

Yes, that's the kind of "function" I intended.

Quote:But if we understand 'function' in the computer science sense of a procedure that takes one argument and returns one result, there are very likely many cin 'functions' such as cin(cin(cin(x)))=sin(x)
One such solution for the HP71 is below ...

Quite clever of you to find the trick, but certainly that's not what I intended as a solution. The trick will work for any function (not just sin(x) ) and for any number of function compositions (not just 3), but it's of no mathematical value or interest whatsoever.

Also, you overdid it a little, there's no need of EXP's or LN's to make it work, simply adding and later subtracting a suitable constant would do just as well (and faster). Finally, your line

      30 IF X=0 THEN Y=0 @ GOTO 70

can be shortened to

      30 IF X=0 THEN END

because if a multi-line user-defined function ends without assigning the return value then it simply returns 0 by default. And  IF X=0  can be replaced by  IF NOT X

Quote:I don't take this solution too seriously :-)

Indeed you shouldn't, neither do I ...

Quote:Still searching for a better one...

Good luck with that, I'm sure you'll succeed and I'm eager to see what you come up with.

Very glad to see you post here, much appreciated. Thanks for your continued interest in my S&SMC's and have a nice weekend.

V.

P.S.: What would it take to lure you into releasing a version of Emu71 which would run on a 32-bit or 64-bit Windows OS, or at least on Android ? Begging ? Bribing ? Taking some relative hostage ? Just plain ol' money ? You tell me, please, it's really affecting my productivity !!