Sequences and Limits
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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.
✓ 15 results · all verified · 7 also independently AI-judged
Every result on this page is machine-checked by a proof checker and read in full by a delegated reviewing agent on the owner's instruction; the judge is an additional, independent cross-model AI review of the proofs. The 8 not AI-judged were verified by owner audit (typically over a confirmed judge false positive), not failures.
1 · Prerequisites
Real Analysis
2 · Logical flowchart
3 · Items
Definition
Sequences of reals: bounded, eventually, frequently, tails, subsequences
Lemma
Convergence depends only on the tail
Lemma
A sequence has at most one limit
Lemma
Every convergent sequence is bounded
Lemma
Every convergent sequence is Cauchy
Lemma
A null sequence times a bounded sequence is null
Theorem
Algebra of limits: sums, scalar multiples, products and quotients
Lemma
Limits preserve non-strict inequalities
Theorem
The squeeze theorem
Lemma
The absolute value is compatible with limits
Definition
Divergence to +∞ and to -∞
Lemma
For positive terms, null and divergence to +∞ are reciprocal
Lemma
A strictly increasing index map satisfies nₖ ≥ k
Lemma
Subsequences inherit the limit
Remark
Conventions for sequences: indexing, eventually, lim, and rational ε
False statement
FALSE: every bounded sequence converges
False statement
FALSE: limits preserve strict inequalities
False statement
FALSE: a convergent subsequence forces the sequence to converge
Sources
- J. K. Hunter, An Introduction to Real Analysis, Ch. 3
- CMU 21-269 notes, Compactness — subsequences
- Sequence (Wikipedia)
- Limit of a sequence (Wikipedia)
- Subsequence (Wikipedia)
- T. Tao, Analysis I, 3rd ed., §6.1
- W. Rudin, Principles of Mathematical Analysis, 3rd ed., Ch. 3
- Cauchy sequence (Wikipedia)
- Reed College Math 112, §7.5 Theorems About Convergent Sequences
- OpenStax Calculus Volume 2, §5.1 Sequences
- T. Tao, Analysis I, 3rd ed., §6.4
- Squeeze theorem (Wikipedia)
- Extended real number line (Wikipedia)
- University of Wisconsin Math 521, Homework 5
- Mathematical induction (Wikipedia)
- T. Tao, Analysis I, 3rd ed., §6.6