Trying to understand the different crosses of Goldendoodles can be very confusing. The one thing you must keep in mind is that the crosses are expressed mathematically.
Genetically, we know that the genes do not follow a mathematical formula when a puppy is conceived. This is why puppies, just like our children, can come from the same parents (or within the same litter for puppies) and have different color or texture of hair, color of eyes, etc. This is also why we can not guarantee coat, color or size.
This explanation will only address the crosses that we produce at Hummingbird Hill Farm. Please remember you aren't just adding the numbers expressed in a parent's generation to come up with a new numerical explanation of the puppy they produce but rather what percent of Poodle or Golden Retriever they bring into the breeding pair.
Here we go....
F1 = Poodle (50%) x Golden Retriever (50%)
F1b = F1 x Poodle (75% Poodle) OR F2 x Poodle (75% Poodle)
F2 = F1 x F1 (50%) x Golden Retriever (50%)
F2b = F1 x F1b (62.5% Poodle)
Multigen = F1b x F1b or F1b x F2b
(Multi generational GD can be bred back to Poodle)