Linear OA(2²⁴⁸, 605, F₂, 52) (dual of [605, 357, 53]-code), using 62 step VarÅ¡amov–Edel lengthening with (r_i) = (6, 3, 3, 2, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 4 times 0, 1, 4 times 0, 1, 4 times 0, 1, 5 times 0, 1, 5 times 0) based on linear OA(2²¹⁶, 511, F₂, 52) (dual of [511, 295, 53]-code), using

• the primitive narrow-sense BCH-code C(I) with length 511 = 2⁹−1, defining interval I = [1,52], and designed minimum distance d ≥ |I|+1 = 53 [i]