Entering a list of comma separated values (i.e. 123, 1.2K, 10K) to find the series and parallel equivalent values.
Connecting any number of resistors in series or parallel will result in an equivalent resistance. This equivalent resistance can be used in place of a single resistor. Although this is not commonly done (simply purchasing the correct value resistor is less expensive and simpler to deal with) there are some reasons why doing so is advantageous.
In a high voltage circuit, using a series connected group of resistors distributes the voltage drop and therefore prevents the resistors from breaking down (resistors do have a voltage rating). In some cases, it is inconvenient to dissipate a large amount of power in a single resistor. Either a series of parallel group or resistors distributes the power dissipation so that each resistor runs cooler. When prototyping and you don’t have the value you need on hand, you can use a series or parallel connecter group to make the value you need.