5 problems

Let a quasi-complementary sequence set (QCSS) have set size $M$, flock size $K$, sequence length $N$, and tightness factor $\rho$. It is asymptotically near-optimal when its correl…

Non-existence conjecture. Let $m\geq 5$ be a prime, $\gamma_1,\gamma_2\in\mathbb Z$, and $n\in\mathbb Z^+$. There does not exist a non-trivial almost $m$-ary NPS of type…

Approximation-ratio conjecture. The ratio satisfies

Let $\mathcal{L}=\bigcup_{N=1}^{+\infty}\{+1,-1\}^N$ be the class of Littlewood sequences, and let $U_N(z)$ denote the associated $L^2$-normalized analytic polynomial for a sequenc…

Lin's conjecture. The sequence $S$ has ideal two-level autocorrelation; that is, if its period is $N$, then