Question: Maple uses a vector instead of a number - dunno why

Hello,

I tried to write a code for CRT-RSA. The encryption is kinda easy and like the normal RSA:

Public key given: (e,N)=(5,851); private key: (d,dcp,dcq,p,q)=(317,29,9,37,23)

with the result:

                      [116, 101, 115, 116]
                       [676, 645, 144, 3]
                      [100, 70, 715, 243]

So, know i tried the following:

that also works pretty fine; dcp and dcq are the CRT-RSA-exponents, and gives:

                        [10, 16, 33, 3]
                          [9, 1, 6, 3]

So now my try for the next step:

but it doesnt work...

the results are:

Why does Maple take the whole vector for y? I dont get it....

Note: if d<sqrt(N), then d=dcq=dcp and the Decryption of normal RSA can be used:

therefore the line:

works as decipher1 already.

So thanks for any help!