Computer-Generated Chess Problem 03358

A 'KRBNN vs kb' mate in 4 chess puzzle or problem (whichever you wish to call it) composed by a computer program, Chesthetica, using the Digital Synaptic Neural Substrate (DSNS) computational creativity approach. It doesn't use endgame tablebases, deep learning or any kind of traditional AI. You can learn more about the DSNS here.

k7/3B1NR1/2N1b3/8/8/8/8/2K5 w - - 0 1
White to Play and Mate in 4
Chesthetica v12.30 (Selangor, Malaysia)
Generated on 18 Jun 2021 at 4:36:43 PMSolvability Estimate = Difficult
Most changes to Chesthetica that result in a slightly higher 'version number' are simply to improve the interface, by the way. White has a decisive material advantage in this position but the winning sequence may not be immediately clear. Leave a comment below, if you like. Solving chess puzzles like this can be good for your health as it keeps your brain active. It may even delay or prevent dementia.
A Similar Chess Problem by Chesthetica: 02761
Solution