Connected (n 4 ) Configurations Exist for Almost All N
نویسنده
چکیده
An (n4) configuration is a family of n points and n (straight) lines in the Euclidean plane such that each point is on precisely four of the lines, and each line contains precisely four of the points. A configuration is said to be connected if it is possible to reach every point starting from an arbitrary point and stepping to other points only if they are on one of the lines of the configuration. In the earlier note it was established that there exist connected (n4) configurations for all n ≥ 21 except possibly in the following cases: n = 32 or n = p or n = 2p or n = p2 or n = 2p2 or n = p1p2, where p, p1, p2 are odd primes and p1 < p2 < 2p1.
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