3 papers
math.CO2023
A criterion for determining whether multiple shells support a -design
Madoka Awada, Reina Ishikawa, Tsuyoshi Miezaki +1
In this paper, we provide a criterion for determining whether multiple shells support a -design. We construct as a corollary an infinite series of -designs using power residu…
math.CO2023
Exceptional designs in some extended quadratic residue codes
Reina Ishikawa
In the present paper, we give proofs of the existence of a 3-design in the extended ternary quadratic residue code of length 14 and the extended quaternary quadratic residue code o…
math.CO2023
Jacobi polynomials and design theory II
Himadri Chakraborty, Reina Ishikawa, Yuuho Tanaka
In this paper, we introduce some new polynomials associated to linear codes over . In particular, we introduce the notion of split complete Jacobi polynomials attac…