I imagine this is intended (though if it's AI-generated "intended" doesn't really apply) as a reference 1999's Cryptonomicon https://en.wikipedia.org/wiki/Cryptonomicon
From that Wikipedia summary:
> Their goal is to facilitate anonymous Internet banking using electronic money and (later) digital gold currency
Digital Cash was invented by David Chaum in 1982, and developed by his company DigiCash in 1990. I read about it years before Cryptonomicon.
Analog circuits (and op-amps just generally) are surprising cool. I know, kind of off on a tangent here but I have integration on the brain lately. You say "4 lines of Python", and I say "1 op-amp".)
A single artificial neuron could be implemented as:
Weighted Sum
Using a summing amplifier:
net = Σ_i (Rf/Ri * xi)
Where resistor ratios set the synaptic weights.
Activation Function
Common op-amp activation circuits:
Saturating function: via op-amp with clipping diodes → approximated sigmoid
Hard limiter: comparator behavior for step activation
Tanh-like response: differential pair circuits
Learning
Early analog systems often lacked on-device learning; weights were manually set with potentiometers or stored using:
Memristive elements (recent)
Floating-gate MOSFETs
Programmable resistor networks