Is this the ideal parallel circuit or is this a combination of series and parallel?
So what you have in that final update is this:







simulate this circuit &ndash; Schematic created using CircuitLab

You have sets of 3 lamps in series. Two of these sets and the power out connector are then in parallel.

This way the next chain of lights gets the full voltage (minus cable losses) and if a bulb goes out only 3 bulbs turn off rather than all of them.