All even proton numbers 2 ≤ Z ≤ 102 have at least two beta-decay stable nuclides, with exactly two for Z = 4 (Be and Be – the former having an extremely short half-life) and 6 (C and C). Also, the only even neutron numbers with only one beta-decay stable nuclide are 0 (H) and 2 (He); at least two beta-decay stable nuclides exist for even neutron numbers in the range 4 ≤ N ≤ 160, with exactly two for N = 4 (Li and Be), 6 (B and C), 8 (N and O), 66 (Cd and Sn, noting also primordial but not beta-stable In), 120 (Pt and Hg), and 128 (Po and Rn – both very unstable to alpha decay). Seven beta-decay stable nuclides exist for the magic N = 82 (Xe, Ba, La, Ce, Pr, Nd, and Sm) and five for N = 20 (S, Cl, Ar, K, and Ca), 50 (Kr, Sr, Y, Zr, and Mo, noting also primordial but not beta-stable Rb), 58 (Mo, Ru, Rh, Pd, and Cd), 74 (Sn, Te, I, Xe, and Ba), 78 (Te, Xe, Cs, Ba, and Ce), 88 (Nd, Sm, Eu, Gd, and Dy – the last not primordial), and 90 (Nd, Sm, Eu, Gd, and Dy).