Multisig question

I’ve been experimenting with a multisig setup on testnet for a while and soon I’m planning to move to multisig on mainnet as well. I’d like to verify/test out as much as I can to make sure I know what I’m doing. I’ve tested multisig wallet recovery, spending, receiving, signing with the wrong key, and a bunch of other things.

What I’m interested in (and could not test out yet) is to broadcast a 2o3 transaction with only 1 signature (all wallets I’ve tried do not even allow pressing “broadcast” with only 1 sig). I’m not even sure if broadcasting is possible since 1 sig would still be missing. But I do not know this for certain. Is it possible, and can I somehow track it being rejected? Could someone point me to the right resources (or explain) where I could do some extra research on how the signing/validating part works for multisig from a mathematical perspective? Would really appreciate it :)