riemann

NS98: projected-cost attempt — no new arithmetic bound

Wall check: Same open gap. Closest results: NS92/93, with the exact projected Gram already in NS53/61/73. The attempted change was to retain the old-coefficient subtraction in a bound on the fixed Mobius direction. No scale-independent average bound was obtained. No theorem node or manuscript version is added.

Attempt and stop condition records the complete projected cross term that remains unestimated. Its diagonal is bounded, by the same elementary separation method used in NS93. This is not a cost bound. Contractivity plus the signed-suffix triangle inequality gives precisely NS92 again; productwise absolute values then reach NS93’s already closed majorant. The smaller projected cost and the actual numerator remain open.

Two finite blocks check the decomposition and its signs, not gain efficiency. Their costs reproduce NS73. The negative signed cross sums at N=16 and 32 are not extrapolated. All complete Gram tails and old/new cross terms are included.

Replay from repository root with the pinned environment:

python evidence/ns98_projected_cost/certify_cost.py --bits 256 --sizes 16 32 --output /tmp/ns98-256.json
python evidence/ns98_projected_cost/certify_cost.py --bits 384 --sizes 16 32 --output /tmp/ns98-384.json
python evidence/ns98_projected_cost/certify_cost.py --bits 384 --sizes 16 32 --cutoff 256 --output /tmp/ns98-cutoff.json
python evidence/ns98_projected_cost/verify.py
maxima --very-quiet -b evidence/ns98_projected_cost/checks.mac

Readable report. Author review only. Both original-evidence gaps and RH/G2 remain open.