In [H. Huang, N.L. Johnson: Semifield planes of order 82, Discrete Math., 80 (1990)], the authors exhibited seven sporadic semifields of order 26, with left nucleus F2 3 and center F2. Following the notation of that paper, these examples are referred as the Huang-Johnson semifields of type II, III, IV, V, V I, V II and V III. In [N. L. Johnson, V. Jha, M. Biliotti: Handbook of Finite Translation Planes, Pure and Applied Mathematics, Taylor Books, 2007], the question whether these semifields are contained in larger families, rather then sporadic, is posed. In this paper, we first prove that the Huang-Johnson semifield of type V I is isotopic to a cyclic semifield, whereas those of types V II and V III belong to infinite families recently constructed in [N.L. Johnson, G. Marino, O. Polverino, R. Trombetti: Semifields of order q6 with left nucleus F q 3 and center Fq, Finite Fields Appl., 14 (2008)] and [G.L. Ebert, G. Marino, O. Polverino, R. Trombetti: Infinite families of new semifields, Combinatorica, 6 (2009)]. Then, Huang-Johnson semifields of type II and III are extended to new infinite families of semifields of order q6, existing for every prime power q.
A generalization of some Huang--Johnson semifields / Johnson, N. L.; Marino, Giuseppe; Polverino, O.; Trombetti, R.. - In: ELECTRONIC JOURNAL OF COMBINATORICS. - ISSN 1077-8926. - 18:1(2011), pp. 1-17.
A generalization of some Huang--Johnson semifields
Giuseppe Marino;R. Trombetti
2011
Abstract
In [H. Huang, N.L. Johnson: Semifield planes of order 82, Discrete Math., 80 (1990)], the authors exhibited seven sporadic semifields of order 26, with left nucleus F2 3 and center F2. Following the notation of that paper, these examples are referred as the Huang-Johnson semifields of type II, III, IV, V, V I, V II and V III. In [N. L. Johnson, V. Jha, M. Biliotti: Handbook of Finite Translation Planes, Pure and Applied Mathematics, Taylor Books, 2007], the question whether these semifields are contained in larger families, rather then sporadic, is posed. In this paper, we first prove that the Huang-Johnson semifield of type V I is isotopic to a cyclic semifield, whereas those of types V II and V III belong to infinite families recently constructed in [N.L. Johnson, G. Marino, O. Polverino, R. Trombetti: Semifields of order q6 with left nucleus F q 3 and center Fq, Finite Fields Appl., 14 (2008)] and [G.L. Ebert, G. Marino, O. Polverino, R. Trombetti: Infinite families of new semifields, Combinatorica, 6 (2009)]. Then, Huang-Johnson semifields of type II and III are extended to new infinite families of semifields of order q6, existing for every prime power q.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


