The nonexistence of regular near octagons with parameters ( s , t , t 2 , t 3 ) = ( 2 , 24 , 0 , 8 ) Bart
نویسنده
چکیده
Let S be a regular near octagon with s + 1 = 3 points per line, let t + 1 denote the constant number of lines through a given point of S and for every two points x and y at distance i ∈ {2, 3} from each other, let ti + 1 denote the constant number of lines through y containing a (necessarily unique) point at distance i − 1 from x. It is known, using algebraic combinatorial techniques, that (t2, t3, t) must be equal to either (0, 0, 1), (0, 0, 4), (0, 3, 4), (0, 8, 24), (1, 2, 3), (2, 6, 14) or (4, 20, 84). For all but one of these cases, there is a unique example of a regular near octagon known. In this paper, we deal with the existence question for the remaining case. We prove that no regular near octagons with parameters (s, t, t2, t3) = (2, 24, 0, 8) can exist.
منابع مشابه
The completion of the classification of the regular near octagons with thick quads
Brouwer and Wilbrink [3] showed the nonexistence of regular near octagons whose parameters s, t2, t3 and t satisfy s ≥ 2, t2 ≥ 2 and t3 = t2(t2 + 1). Later an arithmetical error was discovered in the proof. Because of this error, the existence problem was still open for the near octagons corresponding with certain values of s, t2 and t3. In the present paper, we will also show the nonexistence ...
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تاریخ انتشار 2010