How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Row space, column space, nullspace, row rank, column rank and matrix rank
Definition
Let . Its row space is the span of its rows, its column space is the span of its columns, and its nullspace is
The row rank and column rank are These dimensions are defined because each space is spanned by a finite list. Starting with the empty list, inspect the spanning vectors in order and retain a vector exactly when it is not in the span of those already retained. Induction shows that the retained list is independent and has the same span as the original finite list, so it is a finite basis. The rank of is its row rank; Row rank equals column rank, and both equal the number of pivots proves that it also equals the column rank.
Depends on
The vector space of by matrices over a field, with entrywise operations
Linear combination of a finite list, and the span as the smallest linear subspace containing
Basis of a vector space: a linearly independent spanning subset; and ordered basis: an injective finite list whose image is a basis
Linear independence: a finite list is independent when forces every , and a subset is independent when every injective finite list into is independent
Finite-dimensional vector space, and its dimension ; infinite-dimensional means having no finite basis
The principle of mathematical induction
Matrix equation , its solution set, consistency, homogeneous systems and the augmented matrix