This is about unstable cores that randomly output incorrect calculation and ways to mitigate it via better hardware testing and duplicating parts of the core that can fail often.

I did however thought initially from the title that it's about 1-bit CPUs like the MC14500B Industrial Control Unit (ICU) which is a CMOS one-bit microprocessor designed by Motorola for simple control applications in 1977. It completely lacks an ALU so essentially cannot count, but is designed for PLCs.