Odd-even comparison for Feigenbaum partition lengths ($d|{\Delta }_{2j+1}^{(n)}|\le |{\Delta }_{2j+2}^{(n)}|\le D|{\Delta }_{2j+1}^{(n)}|$)

Odd-address intervals lie in the first image of the central restrictive interval, away from the critical point. The derivative of the Feigenbaum map is bounded above and away from zero there, so the next even interval has comparable length by the mean value theorem. For the wraparound image, $g^{2^n}({\beta }^{n}x)={\beta }^{n}g(x)$ makes its length a fixed fraction $(1-\beta )/2$ of the central interval. Thus the odd and full partition length-power sums differ only by constant factors for each fixed real exponent, and have the same exponential growth rate.