35 名前：o differentiable at each point of A_oo and, for each n >= 0 and for each x in A_n, g is n-times Peano differentiable but not (n+1)-times Peano differentiable at x. Moreover, the complement of A_0 is a first category set and the complement of A_oo is a Lebesgue measure zero set.
NOTE: Norton says "uncountable dense sets" instead of "c-dense in the reals". While it is a little ambiguous what he means (uncountable sets that are dense in the reals, or sets having an uncountable intersection with every open interval) until one gets to the proof, it is clear from the proof (the sets involved are Borel, for instance) that the sets are, in fact, c-dense in the reals.
