You've got 15, 17 and and 19 correct Thermo, but 11 isn't Bowie and 18 isn't Pink Floyd.
Blondini's correct with 13 - Coldplay, Rush of blood to the head
Nickso's right with 16 - Beatles, Abbey Rd and 20 Primal Scream, Screamadelica.
I included that just for you, after your previous...