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.
The zeta sums at 2 and 3 are finite
Statement
For , let , where each positive integer in the summand is identified with its canonical real image. Both sums converge and satisfy .
Statement references
For a nonincreasing nonnegative sequence, converges iff converges: convergence of a nonnegative nonincreasing series is equivalent to convergence of its condensed series.
For , , and for the series diverges: a geometric series with ratio of absolute value less than one converges.
Integer powers : negative integer powers of a nonzero real are defined by reciprocals of natural powers.
The canonical natural of a field: positive natural indices are represented by their canonical real images.
Canonical naturals are positive and strictly increasing: canonical real images of positive naturals are positive.
Facts & Assumptions
Given: An integer and the sequence for positive integer , with integer indices interpreted in by the canonical embedding.
If a nonnegative sequence is nonincreasing, then converges if and only if converges (For a nonincreasing nonnegative sequence, converges iff converges).
A geometric series converges whenever (For , , and for the series diverges).
For a positive integer , its real image is positive, and its negative integer powers are reciprocals of its natural powers (Integer powers , The canonical natural of a field, Canonical naturals are positive and strictly increasing).
Proof
For or , every is positive. If , then : for this follows from , and for from . Taking reciprocals reverses the inequality, so .
For , the condensed term is . For , it is . The final power identities follow by induction on from the recursive definition of natural powers. Thus the condensed series is geometric with ratio or , respectively; [F2] makes both series converge.
The sequence is nonnegative and nonincreasing by step 1.1, and its condensed series converges by step 1.2. Apply [F1] to conclude that converges. Its first term is and all terms are positive, hence .
Depends on
- For a nonincreasing nonnegative sequence, $\sum a_k$ converges iff $\sum 2^k a_{2^k}$ converges
- For $|r| < 1$, $\sum_{k \ge 0} r^k = 1/(1-r)$, and for $|r| \ge 1$ the series diverges
- Integer powers $a^m$
- The canonical natural $\iota(n) = n \cdot 1_F$ of a field
- Canonical naturals are positive and strictly increasing
Used by
Dependency tree · two levels
35 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- Stephen Semmes, Elements of Analysis (standard reference, not scraped)