=== 1. Thom-Porteous calculation ===
c1(U*-Q) = 0
c2(U*-Q) = s11 - s2
[F] = -s11 + s2

=== 2. Round-20 matrix consistency ===
Gvis =
Matrix([[20, 16], [16, 14]])
pairings with [F]=s2-s11: [4, 2]
self-pairing = 2
det Gram(s2,s11,F) = 0

=== 3. Independent flag integrals ===
int_F sigma2*h = 4
int_F sigma11*h = 2
int_F c2(N)*h = 2

=== 4. Sextic del Pezzo root lattice ===
h1^2 = 1
h2^2 = 1
h1.h2 = 2
root Gram on S =
Matrix([[-2, 1], [1, -2]])
det = 3

=== 5. Exceptional root-sector pairing ===
resolution Gram = -3 * Groot =
Matrix([[6, -3], [-3, 6]])
det = 27

Derivation:
gamma_r = jbar_* pbar^* sigma^* r
<gamma_r,gamma_s>_h = - int_Ebar p^*(rs) v_Ebar^2
push pbar_*(v_Ebar^2) = 3 v_Z + 2 h1 + 2 h2
push sigma_*(v_Z) = 1 and sigma_*(1)=0
therefore pairing = -3 int_S r s

=== 6. Blow-up rank bookkeeping ===
left decomposition rank = 6
right decomposition rank = 6

ALL ROUND-22 EXACT CHECKS PASSED.
Spreadsheet runtime warmup failed during python startup
Traceback (most recent call last):
  File "/tmp/tmp.L2TH2Y5coc/artifact_tool_v2-2.8.22/artifact_tool/patches/warm_spreadsheet_runtime_on_startup.py", line 26, in warm_spreadsheet_runtime_on_startup
  File "/tmp/tmp.L2TH2Y5coc/artifact_tool_v2-2.8.22/artifact_tool/spreadsheet_warmup.py", line 785, in warm_spreadsheet_runtime
  File "/tmp/tmp.L2TH2Y5coc/artifact_tool_v2-2.8.22/artifact_tool/spreadsheet_warmup.py", line 720, in _warm_feature_flows
  File "/tmp/tmp.L2TH2Y5coc/artifact_tool_v2-2.8.22/artifact_tool/spreadsheet_warmup.py", line 704, in _warm_collaboration_flows
  File "/tmp/tmp.L2TH2Y5coc/artifact_tool_v2-2.8.22/artifact_tool/generated/interface/models.py", line 32317, in hydrate_crdt_from_proto
  File "/tmp/tmp.L2TH2Y5coc/artifact_tool_v2-2.8.22/artifact_tool/rpc/remote.py", line 749, in __call__
  File "/tmp/tmp.L2TH2Y5coc/artifact_tool_v2-2.8.22/artifact_tool/rpc/client.py", line 150, in call
artifact_tool.rpc.client.RemoteError: hydrateCrdtFromProto requires an empty collaborative document.
