PASS complete lattice basis and order 21 mod seven PASS full length-three eigenchain and nonzero socle-to-top pairing PASS exact images of three generators PASS 343 exact arithmetic unit carries PASS full 343-point orbit decomposition {1: 1, 21: 16, 3: 2} PASS embedded seven-point socle packet PASS semisimple order three and nontrivial order-seven shear PASS lattice-avoidance arithmetic for conductor-three packet Exact audit passed, with no Gamma algebraicity claim. NUMERIC distribution n= 2 n^3= 8 log residual 2.66955535804e-39 expected F(nz) NUMERIC distribution n= 3 n^3= 27 log residual 1.23778995899e-38 expected F(nz) NUMERIC distribution n= 5 n^3= 125 log residual 5.00933800595e-38 expected 1 NUMERIC distribution n= 7 n^3= 343 log residual 9.99377924873e-38 expected F(nz) Numerics are not an interval certificate; the proof is geometric-series Fourier filtering.