The parameters 4-(12, 6, 6) and related t-designs
نویسندگان
چکیده
It is shown that a 4-(12,6,6) design, if it exists, must be rigid. The intimate relationship of such a design with 4-(12,5,4) designs and 5-(12,6,3) designs is presented and exploited. In this endeavor we found: (i) 30 nonisomorphic 4-(12,5,4) designs; (ii) all cyclic 3-(11,5,6) designs; (iii) all 5-(12,6,3) designs preserved by an element of order three fixing no points and no blocks; and (iv) all 5-(12,6,3) designs preserved by an element of order two fixing 2 points.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 7 شماره
صفحات -
تاریخ انتشار 1993