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Exact varying-height escape inside actual odd roots


Statement and purpose

There are finite sets Xi={1}∪YiX_i=\{1\}\cup Y_i of odd squarefree-order roots, in pairwise coprime conductor groups, such that:

  • Each XiX_i is a rational circuit with a unique primitive relation whose magnitudes are {1,Hi}\{1,H_i\}, where Hi=22i−1H_i=2^{2^{i-1}}.
  • Every finite product X1⋯XnX_1\cdots X_n is dissociated.
  • The nested tail-product sets
Dj=⋃n≥jXjXj+1⋯XnD_j=\bigcup_{n\ge j}X_jX_{j+1}\cdots X_n

have least nonzero integer-relation height exactly HjH_j.

  • For each x∈Djx\in D_j, sufficiently late kk satisfies xDk⊂DjxD_k\subset D_j.

Thus height-free flattening fails even for actual root units with injective products and fresh conductors, not just for unrelated scalar configurations. The construction realizes the precise escape in the new coefficient-growth bound. It is not a coloring of the whole root group, and does not obstruct color-adaptive selection under stronger quantitative hypotheses.

1. Moving the coefficient-two seed to arbitrary prime triples

The eight-point seed in S3⊗3S_3^{\otimes3} has primitive kernel generator

(−1,1,−1,1,−1,1,−1,−2)(-1,1,-1,1,-1,1,-1,-2)

on labels 000,012,021,102,110,211,222,001000,012,021,102,110,211,222,001. Its only coefficient of magnitude two is at 001001.

For any distinct odd primes p,q,rp,q,r, enlarge the three simplex factors by duplicating the following layers:

  1. First-coordinate layer 22 into p−2p-2 copies.
  2. Second-coordinate layer 22 into q−2q-2 copies.
  3. Third-coordinate layer 00 into r−2r-2 copies.

The seed's layer-duplication lemma preserves the entire one-dimensional integer kernel: all layer supports are independent, and their coefficients are uniquely determined by their common vector sum. None of these layers contains the distinguished point 001001. Consequently the enlarged set is a circuit in Sp⊗Sq⊗SrS_p\otimes S_q\otimes S_r, with one coefficient −2-2 and all other coefficients ±1\pm1.

The usual coprime cyclotomic tensor identification realizes these columns faithfully by roots. Divide all roots by the distinguished root. The resulting circuit has the form {1}∪L\{1\}\cup L, with LL rationally independent and

2=∑u∈Lϵuu,ϵu∈{±1}.(1)2=\sum_{u\in L}\epsilon_u u,\qquad \epsilon_u\in\{\pm1\}. \tag{1}

All roots are distinct and 1∉L1\notin L.

This construction works on arbitrarily fresh disjoint prime triples. It uses the already proved algebraic seed, not a new search or certificate.

2. Arbitrary powers of two at a unique pivot

Take ss versions of (1) on disjoint conductor triples, and let YY be the full product of their leaf sets LL. Multiplication identifies the tensor of their cyclotomic fields with the compositum. Therefore YY is rationally independent, and multiplication of (1) gives

2s=∑y∈Yϵyy,ϵy∈{±1}.(2)2^s=\sum_{y\in Y}\epsilon_y y,\qquad \epsilon_y\in\{\pm1\}. \tag{2}

The product map is injective. In particular 1∉Y1\notin Y: equality to one would force every factor to equal one, although none belongs to its leaf set. Thus {1}∪Y\{1\}\cup Y is a circuit. Its displayed relation is primitive and unique up to integer multiples, because the leaves form a basis of their span and their coefficients in (2) are all nonzero.

For factor ii, take si=2i−1s_i=2^{i-1} such seeds. Reserve distinct prime triples for all seeds in all factors. This gives

Xi={1}∪Yi,Hi=2si=∑y∈Yiϵi(y)y.(3)X_i=\{1\}\cup Y_i,\qquad H_i=2^{s_i}=\sum_{y\in Y_i}\epsilon_i(y)y. \tag{3}

3. The full products really are independent at the claimed height

Fix a finite index set I⊂{j,j+1,…}I\subset\{j,j+1,\ldots\}, and a relation with coefficients ax∈[−Hj+1,Hj−1]∩Za_x\in[-H_j+1,H_j-1]\cap\mathbb Z on ∏i∈IXi\prod_{i\in I}X_i. The tensor leaf products are a rational basis of the span. For a leaf tuple y=(yi)i∈Iy=(y_i)_{i\in I} and S⊂IS\subset I, let xS(y)x^S(y) be the root tuple using 11 at positions in SS and yiy_i at the other positions. Expand 1=Hi−1∑ϵi(y)y1=H_i^{-1}\sum\epsilon_i(y)y and multiply the coefficient of the basis tuple yy by ∏iHi\prod_iH_i. It is

0=∑S⊂IaxS(y)(∏i∈Sϵi(yi))∏i∈I∖SHi.(4)0=\sum_{S\subset I}a_{x^S(y)} \left(\prod_{i\in S}\epsilon_i(y_i)\right) \prod_{i\in I\setminus S}H_i. \tag{4}

Put B=HjB=H_j. The last products in (4) are distinct nonnegative integer powers of BB, since their exponents are subset sums of the distinct powers 2i−j2^{i-j}. An integer combination of distinct powers of BB, with coefficient magnitudes at most B−1B-1, cannot vanish unless every coefficient vanishes: divide by its least participating power and reduce modulo BB.

Hence axS(y)=0a_{x^S(y)}=0 for every S,yS,y. Every product column occurs in this form (fill the unused leaf positions arbitrarily), so the original relation is trivial. Each such product is (Hj−1)(H_j-1)-independent.

Because every XiX_i contains 11, the finite products defining DjD_j are nested. Every relation has finite support, so DjD_j is (Hj−1)(H_j-1)-independent. The relation on Xj⊂DjX_j\subset D_j has height HjH_j, proving the exact minimum. In particular D1D_1 is dissociated.

For x∈Djx\in D_j, take kk beyond the largest factor used in xx. Then xDk⊂DjxD_k\subset D_j simply uses disjoint sets of factors. Also the DjD_j eventually avoid every prescribed finite conductor-prime set.

4. Rescaling does not manufacture Hall tightness

Every nonzero relation on XiX_i is a multiple of (3). Its magnitude pair is therefore {ti,tiHi}\{t_i,t_iH_i\} for some positive integer tit_i. View these pairs as edges joining positive real labels. A cycle among distinct edges would imply

∏iHiσi=1,σi∈{−1,0,1},σ≠0,\prod_iH_i^{\sigma_i}=1, \qquad \sigma_i\in\{-1,0,1\},\quad \sigma\ne0,

and thus ∑iσi2i−1=0\sum_i\sigma_i2^{i-1}=0, impossible. This also excludes parallel edges. The graph is a forest, so every nonempty subfamily has strictly more incident vertices than edges. No rescaling produces the Hall-tight condition needed for determinant flattening.

This is compatible with the stronger subset-counting theorem: the associated scalar model attains equality at its exact threshold, as computed on that page.

5. Scope

The supports above have product recurrence and a rational dependence in every tail, but they do not cover the whole root group. Indeed D1D_1 is not piecewise syndetic. Given finite multipliers FF, take a factor whose conductor is disjoint from all conductors in FF. Its projection of FD1FD_1 is the proper subset XiX_i of its full conductor group. It cannot contain a translate of that finite subgroup, so FD1FD_1 is not thick. The properness follows, for example, from dissociation of XiX_i and a full prime polygon in the conductor group.

The Hare-based recurrent construction strengthens this diagnostic by making the rational coloring number infinite in every tail. That additional property still does not imply piecewise syndeticity or the actual-color growth inequality.

Fresh-prime duplication, product injectivity, the basis expansion, and tail independence received independent internal checks. No computation was run.