We consider a model for representing innnite-state and para-meterized systems, in which states are represented as strings over a nite alphabet. Actions are transformations on strings, in which the change can be characterized by an arbitrary nite-state transducer. This program model is able to represent programs operating on a variety of data structures, such as queues, stacks, integers, and sys...

In this paper we construct transitive t-designs from the linear groups L(2, q), q ≤ 23. Thereby we classify t-designs, t ≥ 2, admitting a transitive action of the linear groups L(2, q), q ≤ 23, up to 35 points and obtained numerous transitive designs, for 36 ≤ v ≤ 55. In many cases we proved the existence of t-designs with certain parameter sets. Among others we constructed t-designs with param...

With the exception of Bering's plane of order 27, all known odd order flag-transitive affine planes are one of two types: admitting a cyclic transitive action on the line at infinity, or admitting a transitive action on the line at infinity with two equal-sized cyclic orbits. In this paper we show that when the dimension over the kernel for these planes is three, then the known examples are the...

objectives: nouns and verbs are the central conceptual linguistic units of language acquisition in all human languages. while the noun-bias hypothesis claims that nouns have a privilege in children’s lexical development across languages, studies on mandarin and korean and other languages have challenged this view. more recent cross-linguistic naming studies on children in german, turkish, engli...

We show that an action of SL(2, p), p ≥ 7 an odd prime such that 4 6 | (p − 1), has exactly two orbital digraphs Γ1, Γ2, such that Aut(Γi) admits a complete block system B of p + 1 blocks of size 2, i = 1, 2, with the following properties: the action of Aut(Γi) on the blocks of B is nonsolvable, doubly-transitive, but not a symmetric group, and the subgroup of Aut(Γi) that fixes each block of B...

We study locally s-arc-transitive graphs arising from the quasiprimitive product action (PA). prove that, for any (G,2)-arc-transitive graph with G acting quasiprimitively type PA on both G-orbits of vertices, group does not act primitively either orbit. Moreover, we construct first examples that are standard double covers type, answering existence question these graphs.

Previous work of the authors has shown that an important class of locally (G, 2)arc transitive graphs are those for which G acts faithfully and quasiprimitively on each of its two orbits on vertices. In this paper we give a complete classification in the case where the two quasiprimitive actions of G are of different types. The graphs obtained have amalgams previously unknown to the authors and...

and the matrix here is in SL2(R). (This action of SL2(R) on the upper half-plane is essentially one of the models for the isometries of the hyperbolic plane.) The action (1.1) makes sense with C replaced by any field K, and gives a transitive group action of GL2(K) on the set K ∪{∞}. Just as over the complex numbers, the formula (1.2) shows the action of SL2(K) on K ∪ {∞} is transitive. Now tak...