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(OT) Pandigital expression (HP-48,49,50g)
Message #1 Posted by Gerson W. Barbosa on 14 July 2013, 3:47 p.m.

Today is Sunday, but it's also the national date for some members of this forum. The following is kind of a celebration. Notice all digits from 0 through 9 are present and have been used only once. Perhaps FIX 6 should be used for proper day format.

Congratulations !

Edited to correct a language mistake

Edited: 14 July 2013, 4:52 p.m.

      
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #2 Posted by hugh steers on 15 July 2013, 12:38 p.m.,
in response to message #1 by Gerson W. Barbosa

hmm. i'm out by nearly a millenium.

> (0!+sqrt(2)+14*14/75!/(10^6+89))^3
14.07106781186547524400845

must be this mystery (-,75) thing?

any hints.

            
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #3 Posted by Thomas Klemm on 15 July 2013, 1:50 p.m.,
in response to message #2 by hugh steers

Quote:
must be this mystery (-,75) thing?

For you probably rather (-.75)! = 3.62560990822.

Cheers
Thomas

                  
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #4 Posted by Gerson W. Barbosa on 15 July 2013, 2:34 p.m.,
in response to message #3 by Thomas Klemm

Gamma(1/4) would be nicer, but then 1 and 4 had already been used.

DECIMAL POINT IS COMMA :-)

Cheers,

Gerson.

                        
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #5 Posted by Massimo Gnerucci (Italy) on 15 July 2013, 2:42 p.m.,
in response to message #4 by Gerson W. Barbosa

Quote:
DECIMAL POINT IS COMMA

Ditto!

forever and ever amen.

                              
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #6 Posted by hugh steers on 15 July 2013, 3:59 p.m.,
in response to message #5 by Massimo Gnerucci (Italy)

thank you!

the flux capacity is now fixed!

> (0!+sqrt(2)+14*14/-.75!/(10^6+89))^3
14.07201300094483189388136

for a while i was thinking (-1,75)! ie (-1+75i)! which doesnt end up in our spacetime even :-)

                                    
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #7 Posted by Gerson W. Barbosa on 15 July 2013, 4:29 p.m.,
in response to message #6 by hugh steers

Wolfram Alpha will understand (0!+Sqrt[2]+Sq[14]/((-.75)!*(Alog[6]+89)))^3. Originally pandigital expressions would involve only arithmetic operators, but I think the use of Sq, Sqrt etc., when available, makes things a bit more interesting. Sure this is a futile puzzle, but I didn't spend more than thirty minutes on this one :-)

                              
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #8 Posted by Gerson W. Barbosa on 15 July 2013, 4:56 p.m.,
in response to message #5 by Massimo Gnerucci (Italy)

Too bad most programming languages don't have this feature. Back in the day I changed a few bytes in the ROM of my MSX computer. The result was fair enough :-)

      
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #9 Posted by Didier Lachieze on 16 July 2013, 2:49 a.m.,
in response to message #1 by Gerson W. Barbosa

Thanks, this is a nice one! I'm curious about the methodology you used to get it...

            
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #10 Posted by Victor Koechli on 16 July 2013, 3:21 a.m.,
in response to message #9 by Didier Lachieze

Quote:
I'm curious about the methodology you used to get it...
Me too, especially after learning that it only took you 30 minutes to find it. Nicely done!
                  
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #11 Posted by Gerson W. Barbosa on 16 July 2013, 9:50 a.m.,
in response to message #10 by Victor Koechli

keystrokes                       display          comments

14.072013 STO A 14.072013 LN 2.64418793126 ~ pi^2/6 + 1 pi ENTER * 6 / 1 + - 1/X +/- 1340.23897721 nothing interesting after trying a few functions and multiples RCL A sqrt sqrt sqrt sqrt 1.1797018602 again, nothing interesting here RCL A 3 1/x y^x 2.41426761738 ~ sqrt(2) + 1 -- this looks promising 2 sqrt - 1 - 1/x STO B 18499.6728333 3 * 55499.0184999 here we have

(sqrt(2) + 1 + 3/55499)^3 = 14.0720130004

but the 5-digit constant is almost as long as the number we want to represent, also it is not interesting. So let's try other multiples RCL B ENTER ENTER ENTER + 36999.3456666 + + + + + + + + + + + + + 277495.092497

... (very fast keystrokes, I may have missed some interesting results)

+ + + + + + + + + + STO C 3625935.87485 the first four digits match those of gamma(1/4) 4 1/x 1 - x! / 1000089.9067 now we have

(196/(gamma(1/4)*(10^6 + 90)) + sqrt(2) + 1)^3

= 14.0720129999

Again, not interesting enough, but after noticing 196 = 14^2 and gamma(1/4) = (-0.75)! we can try a pandigital expression. There are repeated digits (0, 1 and 2) and 8 is missing. Replacing 90 with 89 solves the latter and eliminates one repeated 0, 1 can be written as 0! and 14^2 as Sq(14). Also Alog(x) can be used for 10^x, so we finally have

(Sq(14)/((-.75)!*(Alog(6) + 89)) + Sqrt(2) + 0!)^3 14 ENTER * .75 +/- x! / 6 10x 89 + / 2 sqrt + 0 x! + 3 yx DISP FIX 6 14.072013 = 14.0720130009

Calculator: HP-32SII
Shifts have been omitted in the keystrokes listing above

                        
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #12 Posted by Thomas Klemm on 16 July 2013, 1:31 p.m.,
in response to message #11 by Gerson W. Barbosa

Quote:
3625935.87485 the first four digits match those of gamma(1/4)

Of course we all know that by heart. Let's be honest: who would not think immediately of that? Gerson, you're just amazing!

Cheers
Thomas

                              
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #13 Posted by Gerson W. Barbosa on 16 July 2013, 2:48 p.m.,
in response to message #12 by Thomas Klemm

Quote:
Quote:
3625935.87485 the first four digits match those of gamma(1/4)

Of course we all know that by heart.


Well, at least the first few digits of a few constants we all do.

Not exactly a scientific methodology, but I guess W|A is not capable of this kind of thing [yet] :-)

Cheers,

Gerson.

                              
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #14 Posted by Victor Koechli on 17 July 2013, 1:31 p.m.,
in response to message #12 by Thomas Klemm

Quote:
Of course we all know that by heart.
You literally took the words out of my mouth. I'm still amazed by Gerson's procedure!
                                    
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #15 Posted by Gerson W. Barbosa on 17 July 2013, 4:29 p.m.,
in response to message #14 by Victor Koechli

A similar "method" yielded 'e*XROOT(12,e^(-3*4)+5.6789)' four years ago (this can be appended to '0+' to include all 10 digits, in ascending order!). And that took only 5 minutes :-)
It was only a matter of luck in both occasions, though. No idea for this year's Pi Approximation Day...

Cheers,

Gerson.

      
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #16 Posted by Gilles Carpentier on 17 July 2013, 1:47 p.m.,
in response to message #1 by Gerson W. Barbosa

:D

Thank's !

I tried to find another pandigital expression for this without success

            
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #17 Posted by Gerson W. Barbosa on 17 July 2013, 4:43 p.m.,
in response to message #16 by Gilles Carpentier

I don't think I would have found this one if I had started by trying to find it in the beginning. As I said, I was lucky I came up with an almost ready-made pandigital expression :-)

Cheers,

Gerson.

      
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #18 Posted by Gilles Carpentier on 18 July 2013, 2:20 p.m.,
in response to message #1 by Gerson W. Barbosa

I'm late but :

'SQ(4!-1)*2*7*(3*6+9-8)-5^0'

In french date format of course ;)

            
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #19 Posted by Gerson W. Barbosa on 18 July 2013, 6:03 p.m.,
in response to message #18 by Gilles Carpentier

Très bien ! And you already have the ones for the next two years :-)

                  
Re: (OT) Pandigital expression (HP-48,49,50g)
Message #20 Posted by Gilles Carpentier on 19 July 2013, 5:59 a.m.,
in response to message #19 by Gerson W. Barbosa

To find this, I use the FACTORS command of the 50G (or the ifactors of the Prime):

140713=140714-1

140713=2*7*19*23²-1

Edited: 19 July 2013, 6:01 a.m.


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