from research import *
s=begin(791,'Sixty-step synthesis checkpoint','What do finite variants add to the common explanation?',{},['C772–790'])
report='# Chronological families: checkpoint C791\n\nSixty sequential steps are complete. The common model now handles three layers: ordered source rows, mode-specific accumulation, and finite variants with named supports.\n\nThe finite regular rule has three binary choices: Sojourn placement215, Terah position60, and Cainan insertion130. Their supports restrict from eight upstream placements to four middle placements and two Abraham placements. Literal Terah and Cainan tables are recovered. The entire aligned SP-with-Cainan/LXX twelve-node birth suffix remains equal in all four matched Sojourn/Terah states.\n\nEqual births do not force equal lives. On that suffix, the local LXX−SP lifespan differences accumulate to574; transferred rounding changes that to570 through two27→25 changes.\n\nTerah supplies the clearest cross-mode distinction: SP textual(70,75), MT/LXX baseline(70,135), and common alternative(130,75) project to different regular/cumulative effects. A lifespan-preserving Terah+60 has zero raw cumulative effect. File51a’s secondary cumulative+60 display block is a separate operation.\n\nRounding commutes with the admitted multiples-of-five moves on their stated rows and domains. Existing coordinate residuals remain unchanged; an inserted Cainan boundary inherits the downstream residual rather than necessarily having zero.\n\nNext: BJ supplies complete index, deletion, and biological/surface paths for testing the same grammar. Native frames, counted versus completed inputs, source versus generated states, and endpoint roles remain explicit.\n'
a=artifact('deliverables/490d_Chronological_Families_Checkpoint_C791.md',report)
finish(s,{'checkpoint':a},'Finite variants fit as bounded choices acting on source-defined supports. Cross-mode behavior depends on the source row lift, not just the variant name.','Reconstruct the complete BJ index object.',{'sixty':791-732+1==60})