论文信息 - A note on triangle-free distance-regular graphs with a2!=0

A note on triangle-free distance-regular graphs with a2!=0

Let @C denote a distance-regular graph with classical parameters (D,b,@a,@b) and D>=3. Assume the intersection numbers a"1=0 and a"2 0. We show that the intersection number c"2 is either 1 or 2, and if c"2=1, then (b,@a,@b)=(-2,-2,((-2)^D^+^1-1)/3).

Chih-wen Weng | Yeh-jong Pan | Chih-wen Weng | Yeh-jong Pan

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