It is shown that SBIBD(4k2, 2k2 + k, k2 + k) and Hadamard matrices with maximal excess exist for k=141, 177, 217, 231. This leaves the following odd k<250 undecided: 47, 71, 77, 79, 103, 107, 127, 131, 133, 139, 151, 163, 167, 179, 191, 199, 209, 211, 213, 215, 223, 227, 233, 237, 239, 243, 249. The method of construction is also presented. © 1994.
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