MinT - Best Known (246−189, 246, s)-Nets in Base 4

Best Known (246−189, 246, s)-Nets in Base 4

(246−189, 246, 66)-Net over F₄ — Constructive and digital

Digital (57, 246, 66)-net over F₄, using

t-expansion [i] based on digital (49, 246, 66)-net over F₄, using
- net from sequence [i] based on digital (49, 65)-sequence over F₄, using
  - Niederreiterâ€“Xing sequence constructionÂ II/III [i] based on function field F/F₄ with g(F) = 49 and N(F) ≥ 66, using
    - T₆ from the second tower of function fields by GarcÃa and Stichtenoth over F₄ [i]

(246−189, 246, 91)-Net over F₄ — Digital

Digital (57, 246, 91)-net over F₄, using

t-expansion [i] based on digital (50, 246, 91)-net over F₄, using
- net from sequence [i] based on digital (50, 90)-sequence over F₄, using
  - Niederreiterâ€“Xing sequence constructionÂ II/III [i] based on function field F/F₄ with g(F) = 50 and N(F) ≥ 91, using
    - a curve from the manYPoints database [i]

(246−189, 246, 238)-Net over F₄ — Upper bound on s (digital)

There is no digital (57, 246, 239)-net over F₄, because

17 times m-reduction [i] would yield digital (57, 229, 239)-net over F₄, but
- extracting embedded orthogonal array [i] would yield linear OA(4²²⁹, 239, F₄, 172) (dual of [239, 10, 173]-code), but
  - residual code [i] would yield linear OA(4⁵⁷, 66, F₄, 43) (dual of [66, 9, 44]-code), but
    - â€œGurâ€ bound on codes from Brouwerâ€™s database [i]

(246−189, 246, 242)-Net in Base 4 — Upper bound on s

There is no (57, 246, 243)-net in base 4, because

7 times m-reduction [i] would yield (57, 239, 243)-net in base 4, but
- extracting embedded orthogonal array [i] would yield OA(4²³⁹, 243, S₄, 182), but
  - the (dual) Plotkin bound shows that MÂ â‰¥ 49 947976 805055 875702 105555 676690 660891 977570 282639 538413 746511 354005 947821 116249 921924 897649 015871 538557 230897 942505 966327 167610 868612 564900 642816 / 61 > 4²³⁹ [i]