No, because there is a difference in meaning then.
Some windows = några fönster
Some of the windows = några av fönstren
In the first one, we're talking generally about some windows somewhere being open. In the second one, we have a certain set of windows, of which some are open.
I am curious about how “någon” etc sounds like negation in English. It’s hard for me wading through svenska etymologi but it seems it might be a shortening of a Germanic phrase literally meaning “know not what thing” ie an unspecified something, could be anything. Old English appears to have had a similar construction. The “nå(g)” would be related to English “no, not”.