@SHIVAS Yes, I did not get the same answer in eqn 22. I do not know what is wrong. If you think an assumption needs to be changed you will need to say which assumption it is and what it needs to be changed to, or change it yourself.

@SHIVAS I get a different transformed answer, which probably can't be inverse-transformed. Please check I didn't make any mistakes.

Download laplace.mw

@dharr If your objective is to follow the derivation in the paper, I can mostly derive the laplace transformed quantities, but I have to guess at the initial conditions - what are they? And why do x and y suddenly appear in the solution? Perhaps you can provide a link to the paper.

@Traruh Synred Somehow Export is being interpreted as ExportMatrix. I can't reproduce this in Maple 2023. @acer suggests you are using 2018, which had Export, but Maple 18 did not (use interface(version) to check your version). You can convert to a 4x1 Matrix and export it as you said, but saving to a .m file will save any Maple object and might be better for your application.

@Traruh Synred I can't figure out what is happening (not a version error) - please upload your worksheet using the green up-arrow in the Mapleprimes editor - choose the file, upload then choose insert link or insert contents.

@sursumCorda I added the timing test for the undocumented Makesplit, and it is not so different from some of the others, I guess there is a lot of overhead for some of these, so it might have been fairer to test with a case that had many more digits.

As for ithprime, according to ?GMP, it makes extensive use of the GMP library isprime, though that is for more digits that your test case here. Actually, processing nextprime a million times in 30 seconds seems pretty good to me!

Download DigitsToArray.mw

@2cUniverse You cannot export a plot structure to a .tiff file. But you can convert it to an Image and then use ImageTools:-Write to write the file - see the code I provided above.

@Scot Gould I used the term "copy contents". The Vector has to be pre-existing; in your example z was not predined as a vector, and by default was a table. copy(v) does copy the vector and is fine at the top level, but within the OPs procedure prev:=copy(curr) still has the problem of assigning to a formal parameter.

@2cUniverse You can convert a plot directly to an Image without writing it to a file, so I think the following does what you want. I made the white background in the plot structure but if you prefer you can add it with PadImage after converting.

Download maketiff.mw

@2cUniverse You can output plots to .gif or .jpeg or .png or  some other image formats (not .tiff). You can set the directory to anything you like for example

path:="C:/Users/dharr/Desktop";
filnam:=cat(path,"/plt",i,".gif");

and omit the base=option if using Export.

@2cUniverse I didn't understand your resolution comments. You could add the white frame as a rectangle behind all elements before exporting the plot in whatever format you want at whatever resolution you want (or as svg or eps vector graphics to later convert to tiff)

Edit: Following makes a square SVG with a white frame.

Download makesvg.mw

@2cUniverse I can't access your zip file. But here is how to make square format .png files (I used Export) - note the size option to give the number of pixels.

Download makepng.mw

Infolevel can be used to show the methods used, though the output is not always easy to understand. In this case further information about the homogeneous methods is given in the odeadvisor help pages.

Download dsolve.mw

@AlexShura OK, so you only entered the sequence to 512. Maple's listtoalgeq still returns fail, so I agree that the oeis result is unexpected and hard to interpret.