How implement a feed forward network with arbitrary node connections in keras?
A possible solution can be found at https://stackoverflow.com/questions/48111217/how-implement-a-feed-forward-network-with-arbitrary-node-connections-in-keras?noredirect=1#comment83198128_48111217

"The suggestion is simply work with many little layers and make as many skip connections as you want. Many parallel layers with 1 node represent well a single layer with many nodes. So you can, for instance, create lots of Dense(1) layers and treat them as nodes. Then you connect them in any way you like."