[FOM] 180:Provable Functions of PA

[William Tait]

On Saturday, June 21, 2003, at 10:02  AM, William Tait wrote:


> On Sunday, June 15, 2003, at 11:42  PM, Harvey Friedman wrote:
>
>> THEOREM 2. The PA provable Delta_0 functions are exactly the Delta_0 
>> functions that are bounded by a <epsilon_0 recursive function.
>
> I can't prove this. Certainly a Delta_0 function bounded by a 
> PA-provably recursive function is provably recursive; but I don't see 
> that it need be Delta_0.

Just in case I'm being suspected of melt-down: of course, I meant that 
I don't see that it need be provably Delta_0.   Bill