A Block Negacyclic Bush-Type Hadamard Matrix and Two Strongly Regular Graphs
نویسندگان
چکیده
A block negacyclic Bush-type Hadamard matrix of order 36 is used in a symmetric BGW(26, 25, 24) with zero diagonal over a cyclic group of order 12 to construct a twin strongly regular graph with parameters v=936, k=375, l=m=150 whose points can be partitioned in 26 cocliques of size 36. The same Hadamard matrix then is used in a symmetric BGW(50, 49, 48) with zero diagonal over a cyclic group of order 12 to construct a Siamese twin strongly regular graph with parameters v=1800, k=1029, l=m=588. © 2002 Elsevier Science (USA)
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ورودعنوان ژورنال:
- J. Comb. Theory, Ser. A
دوره 98 شماره
صفحات -
تاریخ انتشار 2002