Concrete completion decompositions
Abstract
Literal P13 continuations retain the complete ranked vertex word at every height.
Definition 1.1 (Closing vertices).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.closingCount
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.closingCount (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
The closing count records every future closure, irrespective of its rank.
Definition 1.2 (Opening vertices).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.openingCount
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.openingCount (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
The opening count records every future opening.
Theorem 1.3 (Partition of the vertices).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.vertex_count
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.vertex_count (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
A word has length equal to its opening count plus its closing count.
Theorem 1.4 (Endpoint balance).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.continuation_balance
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.continuation_balance (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
Every accepted suffix closes exactly the old survivors, pending openings and future openings.
Theorem 1.5 (Bounds on literal ranks).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.continuation_rank_bound
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.continuation_rank_bound (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
Every closing rank in an accepted suffix is less than its total number of future closures.
Definition 1.6 (Literal completions).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.Completion
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.Completion (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
A completion is a finite word accepted from the given base with zero pending openings and with exactly d closing vertices. Acceptance requires no unfinished endpoint at the end.
Theorem 1.7 (Derived finite support).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.completion_bounds
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.completion_bounds (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
A completion from s has s.size at most d, exactly d minus s.size openings, length twice d minus s.size, and every closing rank below d. These bounds follow from acceptance.
Theorem 1.8 (Finiteness of the literal carrier).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.completion_finite
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.completion_finite (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
Each completion embeds into a fixed length tuple of opening letters and closing ranks below d. Thus its carrier is finite.
Definition 1.9 (Single block counts).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.c
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.c (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
The number c(m,d) counts literal completions from S(m).
Definition 1.10 (Normalized block counts).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.g
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.g (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
The number g(a,b,d) counts literal completions from blocks(a,b). Empty blocks are deleted, so g(a,0,d) equals c(a,d) and g(0,b,d) equals c(b,d).
Theorem 1.11 (Impossible endpoint balances).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.completion_count_zero
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.completion_count_zero (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
A base with more old survivors than future closures has no completion.
Theorem 1.12 (Single block support).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.c_support
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.c_support (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
The count c(m,d) vanishes for m greater than d.
Definition 1.13 (A run of openings).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.openingRun
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.openingRun (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
The word consists of k successive opening vertices.
Theorem 1.14 (Additive closing count).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.closingCount_append
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.closingCount_append (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
Concatenation adds the closing counts of the two literal words.
Theorem 1.15 (Opening runs contain no closures).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.openingRun_closingCount
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.openingRun_closingCount (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
A run of opening vertices contributes zero to the closing count.
Theorem 1.16 (Pending opening transitions).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.accept_openingRun
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.accept_openingRun (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
Reading a run of n openings increases the separate pending count by exactly n.
Theorem 1.17 (Parsing the first closure).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.first_closure_exists
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.first_closure_exists (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
Any word with a positive closing count begins with a run of openings followed by its first closing letter and a remaining suffix.
Theorem 1.18 (Unique first closure parsing).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.first_closure_unique
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.first_closure_unique (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
The initial opening count, first closing rank and suffix are uniquely determined by the literal word.
Definition 1.19 (Descending forced prefix).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedPrefix
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedPrefix (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
For opening multiplicities t1 through ta, the prefix is U to the power t1 followed by rank a minus one, through U to the power ta followed by rank zero.
Theorem 1.20 (Legal forced transitions).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedPrefix_accept
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedPrefix_accept (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
For b positive, reading this prefix from blocks(a,b) with a equal to the multiplicity list length is equivalent to acceptance of the remaining word from S(b plus the sum of the multiplicities).
Theorem 1.21 (Exhaustive forced closure parsing).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedPrefix_exhaustive
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedPrefix_exhaustive (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
Every accepted word from blocks(a,b), with b positive, consists of such a prefix with exactly a forced closures, followed by an accepted single block suffix.
Definition 1.22 (Weak compositions of openings).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.OpeningMultiplicities
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.OpeningMultiplicities (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
A weak composition is a natural valued function on Fin(a) whose sum is t.
Definition 1.23 (Finite prefix and suffix data).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.ForcedData
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.ForcedData (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
The data consists of t at most d, a weak composition into a opening counts, and a concrete completion from S(b+t) with d-a closures.
Definition 1.24 (Bijection on literal two block completions).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedCompletionEquiv
Formalization. D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedCompletionEquiv (✓ std3).
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
For b positive, the finite prefix data and literal completions from blocks(a,b) are equivalent. The inverse exhausts the forced first block. If d is less than a the data is empty, because its suffix would have a positive base and zero closures.
Theorem 1.25 (Finite forced closure count).
Lean statement: D5/S3/Combinatorics/PatternMatchings/P13Completions.g_forced_sum
Proof. Machine-checked in Lean as D5/S3/Combinatorics/PatternMatchings/P13Completions.g_forced_sum (✓ std3). ∎
Source. Repository-derived.
Acknowledgement. Sucharita Biswas, Umesh Shankar, Sivaramakrishnan Sivasubramanian (2026). Matchings and shape-Wilf-Equivalence of sets of patterns of length three I: Triples. DOI: 10.48550/arXiv.2609.08562. URL: https://arxiv.org/abs/2609.08562v1.
Commentary.
For b positive, g(a,b,d) is the sum over t from zero to d of choose(a+t-1,t) times c(b+t,d-a). The weak compositions use the symmetric power carrier, and impossible terms vanish by endpoint balance.
References
- Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.Completion - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.ForcedData - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.OpeningMultiplicities - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.accept_openingRun - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.c - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.c_support - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.closingCount - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.closingCount_append - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.completion_bounds - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.completion_count_zero - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.completion_finite - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.continuation_balance - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.continuation_rank_bound - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.first_closure_exists - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.first_closure_unique - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedCompletionEquiv - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedPrefix - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedPrefix_accept - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.forcedPrefix_exhaustive - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.g - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.g_forced_sum - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.openingCount - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.openingRun - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.openingRun_closingCount - Truth anchor:
D5/S3/Combinatorics/PatternMatchings/P13Completions.vertex_count - Dependency: D5/S3/Combinatorics/PatternMatchings/P13Correspondence