>P=Pink
>D=Dark
>R=Red
Full sequence, double-checked:
P D P R D R R R R P R P R P R R R D R R P R P R
R P R P R R P R P R P D R R P R P R R R R D P D
R D P R R P R D R R R R D R R R D R R P R P R R
R R D P R P R R R R P R P R R R R D P R P R R D
P R P R R R R R R D R P R D R P R R R R R D P R
Patterns noticed:
>The sequence "R P R P R" appears in columns 4 and 11
>The sequence "P R R R D" appears in rows 1, 2, and 4
>The sequence " D P R " appears in rows 4 and 5 and columns 13 and 22
>If continuation is allowed, the sequence "D P R" carries across columns 3 and 4
Intuitions:
>If P R R R D is.—followed by a stop, it's J. If it's-…followed by a stop, it's B.