Dan131m

Anyone wondering about the revision on Black-Scholes model: I'm seeing something like \varphi in some places and \phi in others, so I was trying to fix that. I screwed up the search-and-replace and ended up replacing lowercase phi's with capital ones, so I undid.

Primary ideal

Hi, I am wondering where the alternative "symmetric" definition appears in print. Please answer here: I'll watch. Rschwieb (talk) 19:52, 9 February 2014 (UTC)

• Generally you see this fact written down not as a definition, but as an intermediate step in the proof establishing that the definition at the top of the page is equivalent to the one that says an ideal is primary if the zerodivisors in the quotient are nilpotent. The proof would be in any commutative algebra text that mentions both definitions. I suspect that includes Atiyah-McDonald, but I don't have a copy within reach right now. I checked Eisenbud, but he defines a primary ideal to be an ideal with exactly one associated prime and doesn't include either of the more usual definitions at all. (Probably this definition should be added to the page as well.) --Dan131m (talk) 20:19, 9 February 2014 (UTC)
• In fact, looking over the article I notice that it talks about P-primary ideals but doesn't actually define what it means to be P-primary anywhere! When I save up some free time I'll try to improve that. --Dan131m (talk) 20:24, 9 February 2014 (UTC)