About the only "Maths alternative" aside of having a full-on analog computer would be to have a RandomSource Dual Universal Slope Gen (an exact Eurorack replica of the Serge original) plus some various routing and modification mojo...a MISO or Frap 321, a few VCAs, and maybe a mod or two to the RS module itself. It really IS one of the very few "mandatory" Eurorack modules out there!