912 — The First Three-Normal String Class Lives in Associated Grade
Frozen maximal flag
The first source-derived maximal compatible flag extending Entries 906–909 is
In the Laurent variables of the exact dense momentum kernel this is
The sparse block has the common source factor
so the frozen normalized transition is
Six ordered specializations
The exact Symbolica checker evaluates every order of
All six routes agree and contain no residual normal variable. However, their common ordinary value is
Thus ordinary tetrahedral coherence holds only as the zero map. The rank-one mixed-corner class of Entries 907–909 does not survive ordinary pullback to the maximal flag.
First third-normal grade
Ordinary vanishing does not determine the associated normal grade. Retain the two-normal mixed class, divide by the third normal, and specialize:
Exact reduction gives twelve nonzero entries with
Therefore
Narrow conclusion
The first genuinely three-normal six-point string datum is filtered:
This is direct string-sector evidence for the Marici warning
No new carrier stratum or coefficient divisor is required: the class is generated by the existing associahedral flag and Koba--Nielsen/Pochhammer coefficient calculus.
Scope and next falsifier
This calculation fixes one maximal flag. It does not yet prove that the first-grade class is occurrence-covariant over the complete orbit of maximal six-point flags. The next test is to transport this associated-grade line through the labelled orbit and verify its signed cocycle, including the normal-line character of (A_4-1).