Reference · The Applied Higher-Order Functions catalogue
rainbow.algorithms.proofs.ahof.stieltjes
Stieltjes three-term recurrence for orthogonal polynomials (Kochenderfer Optimization O21.3), a signed-cluster algorithm deferred in August until the signed layer landed. The orthogonal-polynomial recurrence evaluates p_n(x) = (x - alpha) * p_{n-1}(x) - beta * p_{n-2}(x). As a higher-order composition of signed multiply and subtract: `optimization/stieltjes-step x alpha beta previous second = signed/subtract (signed/multiply (signed/subtract x alpha) previous) (signed/multiply beta second)`. The worked theorem proves one step for x=5, alpha=2, beta=1, p1=p2=1 -> (5-2)*1 - 1*1 = 2, by signed cross-product reflexivity. Chains signed-multiply; native and axiom-free on D63. A proved native module; formal ledger crediting is the separate catalog follow-up.
optimization/stieltjes-step
optimization/stieltjes-step : (x₁ x₂ x₃ x₄ x₅ : ℚ) → ℚ
ℚ = signed/SignedRational
optimization/stieltjes-step-worked
optimization/stieltjes-step-worked : → optimization/stieltjes-step (signed/from-nnrat 5) (signed/from-nnrat 2) (signed/from-nnrat 1) (signed/from-nnrat 1) (signed/from-nnrat 1) = signed/from-nnrat 2
= = signed/equivalent: equality of rational values
optimization/stieltjes-step-preserves-zero
optimization/stieltjes-step-preserves-zero : (x alpha beta : ℚ) → optimization/stieltjes-step x alpha beta 0 0 = 0
0 = signed/zero= = signed/equivalent: equality of rational valuesℚ = signed/SignedRational