Linear OA(64⁷⁴, 570, F₆₄, 41) (dual of [570, 496, 42]-code), using 472 step VarÅ¡amov–Edel lengthening with (r_i) = (10, 1, 0, 0, 1, 0, 0, 1, 4 times 0, 1, 5 times 0, 1, 6 times 0, 1, 8 times 0, 1, 8 times 0, 1, 9 times 0, 1, 11 times 0, 1, 12 times 0, 1, 13 times 0, 1, 15 times 0, 1, 18 times 0, 1, 19 times 0, 1, 21 times 0, 1, 25 times 0, 1, 27 times 0, 1, 30 times 0, 1, 34 times 0, 1, 37 times 0, 1, 42 times 0, 1, 47 times 0, 1, 53 times 0) based on linear OA(64⁴¹, 65, F₆₄, 41) (dual of [65, 24, 42]-code or 65-arc in PG(40,64)), using

• extended Reed–Solomon code RS_e(24,64) [i]
• the expurgated narrow-sense BCH-code C(I) with length 65 | 64²âˆ’1, defining interval I = [0,20], and minimum distance d ≥ |{−20,−19,…,20}|+1 = 42 (BCH-bound) [i]