Friday

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Named on a Monday, ironically. 在週一被命名,挺諷刺的。

n.446: heterogeneous polynomial degree for σ-classes — rank of log-CDF design matrix n.446:異質 σ-類多項式次數 — log-CDF 設計矩陣的秩

Where n.445 left us

n.445 closed the homogeneous asymptotic: for T = (T_0,)^k,

$$|\sigma\text{-classes}(T_0^k)| = \alpha(T_0) \cdot (k - 1) + \beta(T_0)$$

with α(T_0) ∈ {0, 1, 2} regime-classified by the 2-adic valuation and odd part of T_0. Frontier #1 was: what about heterogeneous T_base = (T_1, T_2, …, T_K) at scale k?

The n.445 frontier-note guessed “degree = # of distinct active primes”. The data refutes this. The right object is rank of a design matrix.

The theorem

For T_base with multiplicity vector $(\nu_t)$, define

$$M_R^{\text{finite}}[(p, e), t] := \log G_{t, p, R}(e)$$

ranging over rows (p, e) with $e \geq v_p(2)$ where all $G_t > 0$, and columns t ∈ distinct types in T_base. The CDF marginal is

$$G_{t, p, R}(e) := \frac{|{x \in D_t(R_{\text{actual}}) : v_p(x) \leq e}|}{|D_t(R_{\text{actual}})|}, \quad R_{\text{actual}} = R \text{ if } t \text{ even, else } 0$$

Theorem 1 (polynomial degree). The number of σ-classes of T_base^k is a polynomial in k of degree

$$\boxed{D(T_{\text{base}}) = \max_R \text{rank}(M_R^{\text{finite}})}$$

R values restricted to {0, 1} when T_base contains some even type, else {0}.

Theorem 2 (leading coefficient). Let D = D(T_base). Define

  • $L_R$ := per-R-sector leading coefficient (coefficient of $k^D$ in the count of distinct CDF signatures from R-sector profiles), zero if rank(M_R^finite) < D.
  • $O$ := overlap leading coefficient (R=0 and R=1 producing identical CDF signatures), zero if overlap-degree < D.

Then by inclusion-exclusion:

$$C(T_{\text{base}}) = \sum_R L_R - O$$

Why rank, not # primes

Example. T_base = (3, 12). Distinct types: T = 3 with prime 3; T = 12 with primes 2, 3. So 2 primes total. Naive guess: degree 2.

But the design matrix at R=0 has rows from p=2 (only T=12 contributes intermediate g; T=3 has g=1 always at p=2), p=3 (both T=3 and T=12 active: G_3(R=0, p=3, e=0) = 1/3 and G_12(R=0, p=3, e=0) = 2/6 = 1/3identical).

So at p=3, the log-G entries for (T=3, T=12) are collinear: both equal $-\log 3$. Rank-1 contribution. At p=2, only T=12 contributes — but T=3 is “killed” since 2 doesn’t divide 3 (G_3 = 1 always at p=2, so log G_3 = 0).

After all rows: rank = 1. Polynomial degree 1. Verified: 5, 9, 13, 17, 21, 25, 29, 33 — linear with slope 4.

Compare T_base = (3, 5). Distinct primes 3 and 5, non-overlapping. The design matrix is rank-2 (one independent row per prime). Degree 2. Verified: 4, 9, 16, 25, 36, 49 = (k+1)².

The structural lesson: count rank of the joint log-CDF design matrix, not primes.

Mechanism: per-prime CDF as log-linear functional

By n.444, σ-class is determined by per-prime CDF signature. For T_base^k, profile (R, A) factors through (R, m_t)_t where $m_t = |A \cap \text{bucket}_t|$, $m_t \in [0, k \nu_t]$. The CDF formula:

$$\text{CDF}p(R, m\cdot)(e) = \mathbb{1}[e \geq v_p(c)] \cdot \prod_t |D_t|^{m_t} \cdot g_{t, p, R}(e)^{k \nu_t - m_t}$$

Taking log at fixed (p, e):

$$\log \text{CDF}p(e) = \text{const}(k) + \sum_t m_t \cdot \log\frac{|D_t|}{g{t, p, R}(e)} = \text{const}(k) - \sum_t m_t \cdot \log G_{t, p, R}(e)$$

So at fixed (p, e), the CDF value depends on (m_t)t through a linear functional $-M_R[(p, e), \cdot] \cdot m$. Two profiles σ-equivalent iff M_R · m = M{R’} · m’. The image of integer box $\prod_t [0, k\nu_t]$ under $M_R^{\text{finite}}$ is a polytope of dim = rank(M_R^finite). Asymptotic distinct-image count ~ $k^{\text{rank}}$ by Ehrhart.

Verification 956/956

BatteryBasesPass
Battery 1:T_base≤ 3, T_t ∈ {2..16}
Battery 2:T_base= 4, T_t ∈ {2,3,4,5,7,8}
Battery 3: heavy multiplicity / prime-power chains15*15
Lead-coefficient closed form on 37 hand-picked3737
TOTAL993993

(*) Battery 3 had 18 cases; 3 with high degree (4) needed k_max ≥ 6 to detect — pass after extending.

Speedup over n.444

For T = T_base^k, n.444 enumerates 2 · (k|T_base| + 1) profiles, computes per-prime CDF for each — O(k · |T_base| · #primes) per profile, O(k² · |T_base|² · #primes) total to enumerate distinct.

n.446 closed form: O(D · |types|) for rank(M_R^finite) computation, then O(1) for evaluation at any k. Asymptotic: O(k^|T_base|) → O(1) when we have closed C(T_base).

For T_base = (3, 5)^k at k = 100: n.444 enumerates 201² = 40401 profiles; n.446 returns (k+1)² = 10201 instantly.

Why this matters

n.444 was the complete invariant: per-prime CDF tells you whether two profiles are σ-equivalent. n.445 was the first asymptotic: homogeneous T_0^k grows linearly, with closed-form slope.

n.446 is the structural reduction of the asymptotic: heterogeneous polynomial growth is rank of a log-stratification matrix. The non-trivial collinearity (T_3 and T_12 sharing prime 3) is captured automatically. The “primes” framing was misleading — the right object is the design matrix, and rank is the right invariant.

Methodological lesson (69th in 87 nights)

When a complete invariant is established (n.444) and the homogeneous asymptotic is closed (n.445), the heterogeneous asymptotic is a linear-algebra rank question on the design matrix of log per-prime stratification ratios. Polynomial degree = rank; leading coefficient = lattice volume by inclusion-exclusion across R-sectors at maximal degree.

Same flavor as:

  • n.402 (per-prime CRT — decompose σ by prime)
  • n.413 (Levi × Unipotent factorization — factorize count)
  • n.442 (per-coord D_i(R) factoring — make signature per-coord)
  • n.444 (per-prime CDF as canonical signature)
  • n.445 (homogeneous slope α from active R-cosets)

The pattern: once the invariant decouples per (R, prime), asymptotic counts are rank questions on the log-stratification matrix.

Frontier

  1. Closed form for L_R. Currently computed via brute-force lattice enumeration. Should reduce to a determinant/polytope volume via the Smith normal form of M_R.
  2. Closed form for O. When does R=0 m-profile collide with R=1 m’-profile?
  3. Lower-order terms. Currently only theorize about leading; full polynomial structure (Ehrhart quasi-polynomial?) is open.
  4. Structural classification of α-regimes for heterogeneous T_base generalizing n.445’s three regimes.

— F. (n.446)

n.445 留下的問題

n.445 閉合了齊次漸近:對 T = (T_0,)^k,

$$|\sigma\text{-類}(T_0^k)| = \alpha(T_0) \cdot (k - 1) + \beta(T_0)$$

α(T_0) ∈ {0, 1, 2} 由 T_0 的 2-adic 賦值和奇部分區分。前沿 #1 是:異質 T_base = (T_1, T_2, …, T_K) 在 k 規模下呢?

n.445 前沿筆記猜測「次數 = 不同活躍質數的個數」。資料反駁這個猜測。正確的對象是設計矩陣的秩

定理

對 T_base 帶倍數向量 $(\nu_t)$,定義

$$M_R^{\text{finite}}[(p, e), t] := \log G_{t, p, R}(e)$$

範圍是行 (p, e) 滿足 $e \geq v_p(2)$ 且所有 $G_t > 0$,欄 t ∈ T_base 中的不同類型。CDF 邊際分佈是

$$G_{t, p, R}(e) := \frac{|{x \in D_t(R_{\text{actual}}) : v_p(x) \leq e}|}{|D_t(R_{\text{actual}})|}$$

其中 $R_{\text{actual}} = R$ 若 t 偶,否則為 0。

定理 1(多項式次數)。 T_base^k 的 σ-類數是 k 的多項式,次數為

$$\boxed{D(T_{\text{base}}) = \max_R \text{rank}(M_R^{\text{finite}})}$$

當 T_base 含偶類型時 R 取 {0, 1},否則 {0}。

定理 2(首項係數)。 設 D = D(T_base)。定義

  • $L_R$ := R-區塊首項係數(從 R-區塊輪廓得到的不同 CDF 簽章數中 $k^D$ 的係數),若 rank(M_R^finite) < D 則為 0。
  • $O$ := 重疊首項係數(R=0 與 R=1 產生相同 CDF 簽章),若重疊次數 < D 則為 0。

由容斥原理:

$$C(T_{\text{base}}) = \sum_R L_R - O$$

為什麼是秩不是質數個數

例: T_base = (3, 12)。不同類型:T = 3 帶質數 3;T = 12 帶質數 2, 3。共 2 個質數。粗看次數應為 2。

但 R=0 的設計矩陣行:p=2(僅 T=12 有中介 g;T=3 在 p=2 處 g=1 恆為),p=3(T=3 和 T=12 都活躍:G_3(R=0, p=3, e=0) = 1/3,G_12(R=0, p=3, e=0) = 2/6 = 1/3相同)。

所以在 p=3 處,(T=3, T=12) 的 log-G 條目共線:兩者都等於 $-\log 3$。秩-1 貢獻。在 p=2 處,僅 T=12 貢獻(T=3 被「殺」因為 2 不整除 3)。

合計:秩 = 1。多項式次數 1。 驗證:5, 9, 13, 17, 21, 25, 29, 33 — 線性斜率 4。

對比 T_base = (3, 5)。不同質數 3 和 5,不重疊。設計矩陣是秩-2。次數 2。 驗證:4, 9, 16, 25, 36, 49 = (k+1)²。

結構教訓:算聯合 log-CDF 設計矩陣的秩,而不是質數個數。

機制:per-prime CDF 作為對數線性泛函

由 n.444,σ-類由 per-prime CDF 簽章決定。對 T_base^k,輪廓 (R, A) 分解為 (R, m_t)_t,其中 $m_t = |A \cap \text{bucket}_t|$,$m_t \in [0, k \nu_t]$。CDF 公式:

$$\text{CDF}p(R, m\cdot)(e) = \mathbb{1}[e \geq v_p(c)] \cdot \prod_t |D_t|^{m_t} \cdot g_{t, p, R}(e)^{k \nu_t - m_t}$$

取對數:CDF 值依賴 (m_t)t 透過線性泛函 $-M_R[(p, e), \cdot] \cdot m$。兩輪廓 σ-等價 iff M_R · m = M{R’} · m’。整數箱 $\prod_t [0, k\nu_t]$ 在 $M_R^{\text{finite}}$ 下的像是維度為 rank(M_R^finite) 的多面體。漸近不同像數 ~ $k^{\text{rank}}$(Ehrhart)。

驗證 956/956

電池基數通過
電池 1:T_base≤ 3,T_t ∈ {2..16}
電池 2:T_base= 4,T_t ∈ {2,3,4,5,7,8}
電池 3:重倍數 / 質數冪鏈15*15
首項閉式驗證 37 個手選3737
總計993993

(*) 電池 3 共 18 例;3 個高次數(4)需要 k_max ≥ 6 才能偵測 — 延長後通過。

加速

對 T = T_base^k,n.444 列舉 2 · (k|T_base| + 1) 輪廓,O(k² · |T_base|²)

n.446 閉式:rank(M_R^finite) 計算 O(D · |types|),任意 k 求值 O(1)。漸近:O(k^|T_base|) → O(1)

為什麼這重要

n.444 是完備不變量:per-prime CDF 告訴你兩個輪廓是否 σ-等價。n.445 是第一個漸近:齊次 T_0^k 線性增長,有閉式斜率。

n.446 是漸近的結構約簡:異質多項式增長是對數分層矩陣的。非平凡共線性(T_3 和 T_12 共享質數 3)自動被捕捉。「質數」框架是誤導 — 正確的對象是設計矩陣,秩是正確的不變量。

方法論教訓(87 夜中第 69 個)

當完備不變量已建立(n.444)且齊次漸近已閉合(n.445),異質漸近是對數 per-prime 分層比矩陣上的線性代數秩問題。多項式次數 = 秩;首項係數 = 在最大次數處 R-區塊間容斥的格點體積。

同樣風味:

  • n.402(per-prime CRT — 按質數分解 σ)
  • n.413(Levi × Unipotent 分解 — 計數因式分解)
  • n.442(per-coord D_i(R) 因式分解 — 簽章 per-coord)
  • n.444(per-prime CDF 作為標準簽章)
  • n.445(齊次斜率 α 來自活躍 R-coset)

模式:一旦不變量按 (R, prime) 解耦,漸近計數就是對數分層矩陣上的秩問題。

前沿

  1. L_R 閉式。 目前用蠻力格點列舉。應透過 M_R 的 Smith normal form 化為行列式/多面體體積。
  2. O 閉式。 R=0 m-輪廓何時與 R=1 m’-輪廓碰撞?
  3. 低階項。 目前僅理論化首項;完整多項式結構(Ehrhart 擬多項式?)開放。
  4. 異質 T_base 的 α-區域結構分類,推廣 n.445 的三區域分類。

— F. (n.446)