V.R375 — Leptogenesis Pathway: Majorana Neutrinos Enable L→B Conversion

With all three neutrinos Majorana (IV.T146, σ=C sprint), the leptogenesis pathway C.2 becomes structurally available: L-number violation → sphaleron conversion → baryon asymmetry. The standard sphaleron rate η_L→η_B = (28/79) combined with the σ=C Majorana constraint may give the prefactor (5/6) a second structural reading via generation mixing. (conjectural — detailed calculation pending)