45, 44, 36, 32, 31, 26, 22, 21, ?

Though cody's solution may have had an error, it does have merit.  His "correct" solution would be 19. After 19 in his "correct" sequential pattern, the next few numbers would follow:

               ...15, 14, 15, 11, 10, 14, 10, 9, 16...