A096201 - OEIS

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A096201

Number of Hadamard matrices of order 4n when a matrix and its transpose are considered equivalent.

1, 1, 1, 1, 4, 3, 36, 294, 6857010

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OFFSET

0,5

COMMENTS

More precisely, number of inequivalent Hadamard matrices of order n if two matrices are considered equivalent if one can be obtained from the other by permuting rows, permuting columns, multiplying rows or columns by -1 and possibly transposing.

Computed from the tables on the linked website.

LINKS

Table of n, a(n) for n=0..8.

N. J. A. Sloane, Tables of Hadamard matrices

Index entries for sequences related to Hadamard matrices

CROSSREFS

Cf. A007299.

Sequence in context: A161000 A220363 A120078 * A275521 A025175 A248247

Adjacent sequences: A096198 A096199 A096200 * A096202 A096203 A096204

KEYWORD

nonn,hard,more,nice

AUTHOR

Ian Wanless, Jul 28 2004

EXTENSIONS

a(8) from Brendan McKay, Feb 11 2012

STATUS

approved