Computing an order complete basis for M^(infty)(N) and Applications
Pith reviewed 2026-05-25 11:24 UTC · model grok-4.3
The pith
Given two modular functions for Γ₀(N) with coprime pole orders at infinity, an order-complete basis for all such functions can be computed.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
If f and g are modular functions for Γ₀(N) with poles only at i∞ and coprime pole orders, then an algorithm produces an order-complete basis for the space M^∞(N) of all modular functions for Γ₀(N) having poles only at i∞; the same construction also yields two new identities that imply the partition congruence p(11n+6) ≡ 0 mod 11.
What carries the argument
The order-complete basis for M^∞(N), a basis ordered by increasing pole orders at infinity that spans every modular function for Γ₀(N) allowed poles solely at the infinite cusp.
If this is right
- Two explicit new identities are obtained whose coefficients certify the congruence p(11n+6) ≡ 0 mod 11.
- Every modular function for Γ₀(N) with a pole only at infinity belongs to the span of the computed basis.
- The same procedure works for arbitrary level N once suitable input functions f and g exist.
Where Pith is reading between the lines
- The same computational pattern may apply to other congruence subgroups once two functions with coprime pole orders are identified.
- Finding the initial pair f and g for a given N is a prerequisite step whose difficulty is left open by the method.
- The resulting bases could be used to search for further arithmetic congruences satisfied by coefficients of other modular functions.
Load-bearing premise
Two modular functions f and g for Γ₀(N) with poles only at infinity and coprime pole orders must be supplied as input.
What would settle it
For N=11, execute the algorithm on known input functions f and g, extract the resulting identities, and check whether they certify that p(11n+6) is divisible by 11.
read the original abstract
This paper gives a quick way to construct all modular functions for the group $\Gamma_0(N)$ having only a pole at $\tau = i \infty$. We assume that we are given two modular functions $f,g$ for $\Gamma_0(N)$ with poles only at $i \infty$ and coprime pole orders. As an application we obtain two new identities from which one can derive that $p(11n+6)\equiv 0\pmod{11}$, here $p(n)$ is the usual partition function.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper claims to give a quick construction of an order-complete basis for the space M^∞(Γ₀(N)) of modular functions for Γ₀(N) with poles only at i∞, assuming two input functions f,g ∈ M^∞(Γ₀(N)) with coprime pole orders at infinity are already available. It applies the method to produce two new identities implying the known congruence p(11n+6) ≡ 0 (mod 11).
Significance. If the construction is valid once suitable f and g are supplied, the approach could streamline computation of bases for these spaces and facilitate discovery of arithmetic relations, as illustrated by the partition-function identities. The explicit identities add concrete value even if the underlying congruence is classical.
major comments (2)
- [Abstract] Abstract and first paragraph: the central construction is stated to require two input functions f,g with coprime pole orders, yet no general algorithm, recurrence relation, or existence proof is supplied for producing such a pair for arbitrary N; this prerequisite is load-bearing for the title claim of 'computing' an order-complete basis.
- [Application] Application section: the derivation of the two new identities for N=11 must explicitly verify that the chosen f and g satisfy the coprime-pole-order hypothesis and include the intermediate steps that convert the basis into the stated partition identities.
minor comments (1)
- [Abstract] Notation for the space M^∞(N) should be defined on first use and related explicitly to the standard notation M^∞(Γ₀(N)).
Simulated Author's Rebuttal
We thank the referee for the careful reading and constructive comments. We address each major point below.
read point-by-point responses
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Referee: [Abstract] Abstract and first paragraph: the central construction is stated to require two input functions f,g with coprime pole orders, yet no general algorithm, recurrence relation, or existence proof is supplied for producing such a pair for arbitrary N; this prerequisite is load-bearing for the title claim of 'computing' an order-complete basis.
Authors: The abstract and introduction already state explicitly that the construction assumes two such input functions f and g are given. The paper's contribution is the efficient method to obtain the order-complete basis once suitable f and g are available; it does not claim or attempt a general algorithm for producing the inputs themselves for arbitrary N. We will revise the abstract to emphasize this conditional nature more prominently, thereby aligning the presentation with the title. revision: partial
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Referee: [Application] Application section: the derivation of the two new identities for N=11 must explicitly verify that the chosen f and g satisfy the coprime-pole-order hypothesis and include the intermediate steps that convert the basis into the stated partition identities.
Authors: We will revise the application section to include an explicit verification that the pole orders of the chosen f and g for N=11 are coprime, together with the intermediate steps that produce the two new identities and the resulting partition congruence. revision: yes
Circularity Check
No circularity; derivation is conditional on explicitly stated external inputs f and g
full rationale
The paper states upfront that it assumes two modular functions f and g with coprime pole orders are already given as inputs, then constructs the basis from them. No equations, self-citations, fitted parameters, or reductions of the claimed output back to those inputs by construction are visible in the abstract or described claims. The method is therefore self-contained as a conditional algorithm rather than a closed loop that renames or re-derives its own prerequisites.
Axiom & Free-Parameter Ledger
Reference graph
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