The device [electronic I Ching calculator] also functioned as an ordinary calculator, but only to a limited degree. It could handle any calculation which returned an answer of anything up to 4.... anything above 4 it represented merely as "A Suffusion of Yellow." Dirk was not certain if this was a programming error or an insight beyond his ability to fathom, but he was crazy about it anyway, enough to hand over twenty pounds of ready cash for the thing.

Ch. 10, p. 104-105 - The Long Dark Tea-Time of the Soul (1988)