96 citations · 292 across the 62 of their papers we have counts for
5 papers · 1 filter
Constellations in prime elements of number fields
Wataru Kai, Masato Mimura, Akihiro Munemasa +2
Given any number field, we prove that there exist arbitrarily shaped constellations consisting of pairwise non-associate prime elements of the ring of integers. This result extends…
Bordered complex Hadamard matrices and strongly regular graphs
Takuya Ikuta, Akihiro Munemasa
We consider bordered complex Hadamard matrices whose core is contained in the Bose-Mesner algebra of a strongly regular graph. Examples include a complex Hadamard matrix whose core…
Signed analogue of line graphs and their smallest eigenvalues
Alexander L. Gavrilyuk, Akihiro Munemasa, Yoshio Sano +1
In this paper, we show that every connected signed graph with smallest eigenvalue strictly greater than and large enough minimum degree is switching equivalent to a complete g…
Ternary codes, biplanes, and the nonexistence of some quasi-symmetric and quasi-3 designs
Akihiro Munemasa, Vladimir D. Tonchev
The dual codes of the ternary linear codes of the residual designs of biplanes on 56 points are used to prove the nonexistence of quasi-symmetric 2- and 2- d…
A note on Assmus--Mattson type theorems
Tsuyoshi Miezaki, Akihiro Munemasa, Hiroyuki Nakasora
In the present paper, we give Assmus--Mattson type theorems for codes and lattices. We show that a binary doubly even self-dual code of length 24m with minimum weight 4m provides a…