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). .. ,

. , 85 7 Recover the code C pub from the invariant code

. .. Orderboundtable,

.. .. , 71 4.2 Number of variables of the polynomial system after reduction, List of Tables 3.1 Average time for Algorithm 3 with ? diagonalizable in F q

. , Estimation of the minimum distance

, We define L(G + ?Q, Definition A.1. Let Q be a rational place and G be a rational divisor of F q (?)

, We call H(Q

, G) the set of G-non-gaps at Q. The set ?(Q; G) := Z ?v Q (G)?deg(G) \ H(Q; G) is called the set of G-gaps at Q

, the set of gaps at Q. Further, note that if i ? H(Q; F 1 ) and j ? H(Q; F 2 ), then i + j ? H(Q; F 1 + F 2 ). Finally, observe that the theorem of Riemann-Roch implies that the number of G-gaps at Q coincides with the genus of ?

G. )|-=-g,

, If i < ? deg(G) then deg(G + iQ) < 0 and L(G + iQ) = {0}. So in the previous definition we can write L(G + ?Q) = i?? deg(G) L(G + iQ). Further, note that for any a ? Z we have

, G + aQ) = H(Q; G) as well as ?(Q

G. +-aq)-=-?(q;-g),

. , Let Q be a rational place and let F 1 , F 2 be two divisors of ?

, Q be a rational place not occurring in D, and F 1 , F 2 be two divisors disjoint from D. Suppose that C L, Let D = P 1 + · · · + P n be a divisor that is a sum of n distinct rational places of F q (?)

, + F 2 ) of C L (D, F 1 + F 2 ) ? satisfies d(F 1 + F 2 ) ? min{?(Q; F 1

C. , G. , and .. , Q (N ) of not necessarily distinct rational places, none occurring in D, such that

G. +-q-;-+-·-·-·-+-q, 0), where the minimum is taken over all i satisfying 1 ?

=. and G. , ) + · · · + Q (i) ). The well known Goppa bound is a direct consequence of Proposition A.1 as shown in

?. , If the support of a divisor G consists of one rational point not in supp(D), the code C L (D, G) is called a one-point AG code. Similarly, if G = a 1 Q 0 + a 2 Q ? , the code C L (D, G) is called a two-point code. By slight abuse of notation, the dual of a one-point code (resp. two-point code) are sometimes also called one-point (resp. two-point) codes, but we will only use the terminology for the codes C L (D, G), n be a sum of distinct rational places, let Q be a rational place not occurring in D, and let F 1 , F 2 be two divisors disjoint from D. Then ?(Q; F 1

, ) for all t satisfying 0 ? t ? min{b 2 ? 1, 2g ? 1 ? a 1 ? a 2 }. In the next theorem we show that the order bound in the same situation improves upon the Goppa bound by at least one as well. Therefore, our results will automatically include all results in [CT16b] as a special case

, Q 2 ) for all t satisfying 0 ? t ? min{b 2 ? 1, 2g ? 1 ? a 1 ? a 2 } is equivalent to the statement that ? Q 1 ,Q 2 (b 1 ) ? b 2 or ? Q 1 ,Q 2 (b 1 ) < b 2 ?1?min{b 2 ?1, 2g?1?a 1 ?a 2 }. With these reformulations in mind

A. Theorem,

, ) < b 2 ? 1 ? min{b 2 ? 1, 2g ? a 1 ? a 2 }, then ?(Q 2

, Combining Remark 23 with (the proof of) Lemma A.2 we see that ?(Q 1 G) ? 2g(?) + 2. Indeed, the term q Q 1, vol.223, p.220

A. Table, ) for which dimension of the form C L (D, a 1 Q 0 ) ? or C L (D, a 2 Q ? ) ?. The four entries in boldface indicate new improvements on the MinT tables, Table A.1 gives for q = 2