Talk:Elementary recursive function

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I think it should be stated earlier in the article and more clearly that Elementary functions are a strict subset of Primitive Recursive functions. It isn't explained until the last paragraph of the article, and the summary at the top of the article is misleading in this regard.

I added a bit to the summary. Hopefully it clarifies and doesn't just confuse more hah. But you're right: there should be something in the summary to provide a clear relationship to the primitive recursive functions. Mofoburrell 20:50, 8 September 2007 (UTC)[reply]

It seems that the given definition is wrong: there is no way to implement decreasing functions. I don't see either how to encode f(x,y)=x+y. And the hint concerning the repetition of successors do not apply here since we do not have any iteration scheme. —Preceding unsigned comment added by 140.77.13.170 (talk) 14:43, 30 March 2009 (UTC)[reply]

Yeah, it was missing a base function.Ben Standeven (talk) 05:08, 24 December 2009 (UTC)[reply]

I don't see how to encode non ultimately monotonous functions like "n mod 2" with the given definition. Am I missing something ? --Xoff777 (talk) 04:33, 5 June 2015 (UTC)[reply]

Examples?

An example for ELEMENTARY\NP would be nice… --Chricho (talk) 16:44, 4 January 2011 (UTC)[reply]

That makes no sense. ELEMENTARY is a class of functions, NP is a class of languages.—Emil J. 22:17, 10 April 2015 (UTC)[reply]