4 problems

Ding's conjecture. The minimum distance of the primitive BCH code ${\mathbf{C}}_{(q,q^m-1,q^t+1,1)}$ always equals its Bose distance $d_B$.

Let $m=2^l e>2$, where $2\nmid e$ and $l\geq1$, and let $\mathcal{C}_{\mathcal{D},i}$ denote the cyclic code associated with the sequence family $\mathcal{D}$. Let $h$ be the param…

Let $m=2^l e>2$, where $2\nmid e$ and $l\geq1$, and let $\mathcal{C}_{\mathcal{S},i}$ denote the cyclic code generated by $M_{\mathcal{S},i}(x)$. Define … Here $d(\mathcal{C})$ den…

Let $X$) be a real normed linear space, let $S\subset X$ be a subspace, and let $y\in X$. The annihilator of $S$ in the predual is denoted by $S^\perp$. Minimum distance duality co…