kinda confused about your question, but a simple interpretation is: an AP (Access Point) can provide many connections, usually something on the order of 256. Or did you mean something else? BTW, a wireless router is a router with an AP built-in.
<i>It's always the one thing you never suspected.</i>
A router would have the number limitation based on it's ip range. AP's, theoretically, wouldn't or shouldn't have a realistic limit on the client associations. They are wireless hubs. In reality, you would only put as many nodes and the overall bandwidth could accomodate. Some actually do have a limit to the associations they can accept. Cisco's AP's for instance is 1024. Now if you know anything about networking or wireless networking, it is easy to understand how that number would never ever ever come into play on one AP. On a 802.11b AP, 10 or so associations, if transferring files, can choke it. If all your doing is sharing a broadband connection you can put as many clients on as you'd want sharing that internet connection.
On my access point, I think it said 128 connections max, but anything past 32 would drop speed from 11Mbps to 5Mbps and lower. But if they were all accessing at the same time kwebb68 is right, they would probably get really bogged down.