Linear OA(4⁶⁹, 286, F₄, 22) (dual of [286, 217, 23]-code), using 216 step VarÅ¡amov–Edel lengthening with (r_i) = (6, 3, 2, 2, 1, 1, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 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, 5 times 0, 1, 5 times 0, 1, 5 times 0, 1, 6 times 0, 1, 7 times 0, 1, 7 times 0, 1, 7 times 0, 1, 9 times 0, 1, 9 times 0, 1, 10 times 0, 1, 10 times 0, 1, 12 times 0, 1, 12 times 0, 1, 13 times 0, 1, 15 times 0, 1, 16 times 0) based on linear OA(4²², 23, F₄, 22) (dual of [23, 1, 23]-code or 23-arc in PG(21,4)), using

• dual of repetition code with length 23 [i]