Counting additive triples for cubic AR labeling
Abstract
The additive-triple cardinality and the strict cubic-labeling union bound.
Definition 1.1 (The free additive triples).
Lean statement: D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.additivePairs
Formalization. D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.additivePairs (✓ std3).
Source. Repository-derived.
Commentary.
The finite set contains the smaller ordered pair of labels in a triple a<b<a+b with all labels in the interval from three to m. It is formed as disjoint rows indexed by a minus three.
Theorem 1.2 (The additive-triple constraints).
Lean statement: D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.mem_additivePairs
Proof. Machine-checked in Lean as D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.mem_additivePairs (✓ std3). ∎
Source. Repository-derived.
Commentary.
For m at least six, membership of the pair (a,b) is equivalent to three at most a, a less than b, and a+b at most m.
Theorem 1.3 (A square upper bound).
Lean statement: D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.four_mul_card_additivePairs_le
Proof. Machine-checked in Lean as D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.four_mul_card_additivePairs_le (✓ std3). ∎
Source. Repository-derived.
Commentary.
Four times the number of additive pairs is at most the square of m-5. This follows from the rectangular cardinality and the nonnegative square of the difference between its side lengths.
Theorem 1.4 (The factorial-weighted strict union bound).
Lean statement: D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.bad_count_lt_factorial
Proof. Machine-checked in Lean as D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.bad_count_lt_factorial (✓ std3). ∎
Source. Repository-derived.
Commentary.
For m at least twelve, 3n=2m, and 4t at most (m-5)^2, the sum of (m-3)!, 2(2m-7)(m-4)!, and 6(n-3)t(m-5)! is strictly below (m-2)!. Multiply the normalized inequality by the positive factorial (m-5)! and use the factorial recurrence.
References
- Truth anchor:
D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.additivePairs - Truth anchor:
D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.bad_count_lt_factorial - Truth anchor:
D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.four_mul_card_additivePairs_le - Truth anchor:
D5/S3/Combinatorics/EdgeLabeling/CubicARGraphArithmetic.mem_additivePairs