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A158863 Maximal excess of a 3-normalized Hadamard matrix of order 4n. 0
4, 8, 36, 32, 76, 72, 124, 128, 180, 200, 244, 288, 316 (list; graph; refs; listen; history; text; internal format)



The excess of a {-1,1} matrix is the sum of its elements. A Hadamard matrix is 3-normalized if its first three rows contain an even number of entries -1 in each column. 3-normalized Hadamard matrices of order 4n with large excess can be used to construct large-determinant {-1,1} matrices of order 4n+1.


Table of n, a(n) for n=1..13.

W. P. Orrick and B. Solomon, The Hadamard Maximal Determinant Problem (website)

W. P. Orrick and B. Solomon, Large-determinant sign matrices of order 4k+1, Discr. Math. 307 (2007), 226-236.


Cf. A004118.

Sequence in context: A149109 A266676 A046056 * A074736 A044829 A338086

Adjacent sequences: A158860 A158861 A158862 * A158864 A158865 A158866




William P. Orrick, Mar 28 2009



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Last modified December 9 10:28 EST 2022. Contains 358700 sequences. (Running on oeis4.)