Wallis gamma remainder functions
Abstract
Strict monotonicity of three Wallis gamma remainders.
Theorem 1.1 (The three strict monotonicity inequalities).
Lean statement: D5/S3/Analytic/WallisRemainder/Result.result
Proof. Machine-checked in Lean as D5/S3/Analytic/WallisRemainder/Result.result (✓ std3). ∎
Resolves. Problems/mahmoud-mortici-2026-wallis-remainder-monotonicity (proved) by D5/S3/Analytic/WallisRemainder/Result.result.
Source. Repository-derived.
Acknowledgement. M. Mahmoud and C. Mortici (2026). Structural Properties, Complete Monotonicity, Bounds, and Analytic Approximations with Bounded Remainders for a Wallis-Type Gamma Ratio. DOI: 10.1007/s00025-026-02697-2. URL: https://link.springer.com/article/10.1007/s00025-026-02697-2.
Commentary.
For every pair of positive real numbers x<y, the functions defined in Defs satisfy mu(x)<mu(y), chi(x)<chi(y), and theta(y)<theta(x). The logarithm of the Wallis ratio and the inner reciprocal denominator defining mu are nonzero at every positive argument.
Let S_P and S_Q be the Stieltjes transforms of the positive spectral law and its size-biased law. The mean of P is m=1/24 and its variance is 31/2880. The mean of Q is c=3/10 and its variance is 771/5600. Integration of v/(z+v)=1-z/(z+v) gives z S_P(z)=1-m S_Q(z). The analytic representation of the logarithmic remainder and exact algebra then identify theta(x)=-G_P(x^2), chi(x)=G_Q(x^2), and mu(x)=H_Q(x^2)-m, where G is the normalized Jensen remainder and H(z)=1/S(z)-z.
Both laws have finite positive variance. Their normalized Jensen remainders increase strictly, and the inverse transform offset of Q increases strictly. Since squaring increases strictly on positive reals, the three stated comparisons follow with their respective signs. Positivity of both transforms and the size-bias identity also prove both nonvanishing assertions for mu.
References
- Truth anchor:
D5/S3/Analytic/WallisRemainder/Result.result - Dependency: D5/S3/Analytic/WallisRemainder/Defs
- Dependency: D5/S3/Analytic/WallisRemainder/Laplace
- Dependency: D5/S3/Analytic/WallisRemainder/Measure
- Dependency: D5/S3/Analytic/WallisRemainder/Stieltjes