Talk:Combinatorial class

AfD?

I propose this article be deleted. There is a reason there are no refs here - this is just not a standard mathematical definition, I think. I made a GoogleBooks search and found a dozen of different uses of "combinatorial class", including this one, but none in a serious Combinatorics textbook. Sorry. Any defenders?

P.S. Set of equal size are not "isomorphic" but "equinumerous". Igorpak (talk) 20:04, 19 March 2013 (UTC)

I disagree. Sources were not hard to find, and the concept of different types of combinatorial object having the same counting sequence is an important one under whatever name you want to call it. The serious combinatorics book you should have been looking in is the one by Flajolet and Sedgewick. As for "equinumerous", (1) that refers to one set, not a whole counting sequence, and (2), "isomorphic" is the word used by Flajolet and Sedgewick, and we have to go with what the literature says rather than making up our own preferred terminology. —David Eppstein (talk) 21:07, 19 March 2013 (UTC)

David, I don't make up terminology. I know WP rules and don't appreciate being condescended either. I am saying that "equinumerous" is standard and more accepted in my field, even if [FS] book uses something else. See e.g. [1], [2], [3], [4], [5], etc., all used for infinite families of permutations, trees, partitions, etc.

Now, in my opinion, "combinatorial class" needs many more refs independent of Flajolet who was a big proponent of the term, to convince me that it's a legitimate term in wide use. As I understand WP rules, the burden of proof is on proponents/defenders of this article, with [FS] being perhaps too recent to make an impact. By WP:CBALL and WP:RECENT, I say it's too early to suggest this term already has or will become standard.

You see, just because one famous person is using some terminology does not make it standard. My favorite example is "perm" introduced by Don Knuth for "permutation", along with $\sigma ^{-}$ notation for $\sigma ^{-1}$. Needless to say, these notations didn't take. Igorpak (talk) 04:18, 20 March 2013 (UTC)