## Appendix E. SKL precession square: 25921 and the 24+25 partition

**Added:** 25 September 2026. **Frame:** normal Gear 2; the parent report’s t/n and no-year-zero conventions. The SKL also retains declared local **−2/0/+2-year** companions, distinct from its **−720/0/+720** macro field. The calculations below hold the normal central SKL state fixed. [E2, §2.2]

### E.1 The established 259210 basis

File_21 already documents **262086 BC → 2876 BC = 259210 = 490×529 = 10×161²**, and **25921 = 161² = 49×529**. These precede the present axis comparison. [E1]

With full phases, **262087t/262086n BC → 2877t/2876n BC** gives:

$$262087-2877=262086-2876=259210=10\times25921.$$

### E.2 One precessional Great Year, then the additional year

Hold the SKL Long Flood at **27367t/27366n BC**. Its interval to Exodus **1447t/1446n BC** is the repository’s **25920-year precessional Great Year**. One further year reaches the Tabernacle pair **1446t/1445n BC**, giving **25921 = 161²**. [E1, §15.2; E2, §5.4]

Applying the report’s previously selected **12696 = 24×529** forward translation leaves the generated point **14671t/14670n BC**:

| Interval, all endpoints BC | Tishri calculation | Nisan calculation | Years |
|---|---:|---:|---:|
| SKL Flood → Exodus | 27367−1447 | 27366−1446 | **25920** |
| SKL Flood → Tabernacle | 27367−1446 | 27366−1445 | **25921 = 49×529** |
| SKL Flood → generated point | 27367−14671 | 27366−14670 | **12696 = 24×529** |
| Generated point → Tabernacle | 14671−1446 | 14670−1445 | **13225 = 25×529 = 115²** |

Thus:

$$\boxed{25920+1=25921=12696+13225=(24+25)\times529.}$$

The complementary square admits two exact **25/23** expansions, replacing one factor of 23 at each step:

$$13225=25\times23^2
\xrightarrow{\times25/23}14375=25^2\times23
\xrightarrow{\times25/23}15625=25^3=125^2=5^6.$$

The same generated point is **13224** years before Exodus and **13225** before the Tabernacle endpoint; the one-year distinction is retained.

### E.3 The existing 13×529 Mirror connection

Within the MT cumulative Shem-birth seven-year field, select **5433t/5432n BC**, whose ordinary reflection is **AD 5432t/5433n**. This is the **Shem-birth / Noah-death boundary**, not Noah’s birth. [E3; E4]

From the same Tabernacle pair, both components give **6877 = 13×529**:

$$1446t\text{ BC}\rightarrow\text{AD }5432t:
\quad1446+5432-1=6877,$$
$$1445n\text{ BC}\rightarrow\text{AD }5433n:
\quad1445+5433-1=6877.$$

Consequently, SKL Flood → Tabernacle → reflected Shem birth spans **(49+13)×529**:

$$27367+5432-1=27366+5433-1=32798=62\times529.$$

The adjacent Shem reflection **AD 5431t/5432n**, compared with reflected Conquest **AD 1406t/1407n**, supplies the related factor pattern:

$$5431-1406=5432-1407=4025=161\times25
\xrightarrow{\times25/23}4375=7\times5^4.$$

It belongs to **3703 → 4025 → 4375**, precisely one seventh of **25921 → 28175 → 30625**, with each arrow applying 25/23. These nested factor relationships motivate further comparison of the dated endpoints.

**Scope:** the new finding connects the already documented SKL square to the report’s established 12696 width and the MT Mirror field. The proposed 126960/253920 Creation-scale extensions remain deferred. Appendix E’s arithmetic was checked separately; Appendix B’s 855-check count belongs to the original report.

**Existing repository references**

- **[E1] File_21 — SKL Unified Protocol:** §14.1 (259210); §25, Note A (25920+1, 161², and the tenfold relation); §15.2 (1445 BC Tabernacle endpoint).
- **[E2] File_34 — Unified Chronology: SKL, Berossus, Bible:** §5.4 (27366 BC → 1446 BC = 25920); §2.2 (local ±2 and macro ±720 Gear fields).
- **[E3] File_18 — Chronological Data Tables:** §6A, MT cumulative trunk; Shem’s **5436–5429 BC** envelope and Noah’s preceding 950-year lifespan.
- **[E4] File_09 — Cumulative Architecture:** Appendix A.3, phase-preserving reflection and civil cross-axis arithmetic **BC+AD−1** for matching seasonal components.