I need to write prolog to find the solution of the following question:

1)You have six colored balls: 4 black, 1 red and 1 blue.

2)There are no more than 2 black balls in a row.

perm2 :- permutationQ([black,black,black,black,red,blue],[A,B,C,D,E,F]), ((A==black -> B==black), (D==black -> E==black); (C==black -> D==black), (E==black -> F==black));

this is what I thought of so far, are there more ways to go to finish the code? And which letters cannot be Red or Blue??

And I also need to calculate how many solutions exist and the conditions are:

1)Balls with the same color are indistinguishable.

2)All balls are distinct, even those with the same color.

It would be nice with explanations.