if you ask it say generate a piece following Dmaj9/Amaj/Bmin/Bmin it will understand that Dmaj9/Amaj/Bmin/Bmin will be the seed sequence to the RNN. Of course,

if you ask it say generate a piece following Dmaj9/Amaj/Bmin/Bmin it will understand that Dmaj9/Amaj/Bmin/Bmin will be the seed sequence to the RNN. Of course, the network might ignore the seed, or if it's overfitting it will produce a chunk of the training sample which has this sequence in it, but you can definitely specify the starting point (and you usually do with RNNs).