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

Offset: 0

Author

Ian Wanless, Jul 28 2004

Keywords

• nonn
• hard
• more
• nice

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

• N. J. A. Sloane, Tables of Hadamard matrices
• Index entries for sequences related to Hadamard matrices

Crossrefs

Cf. A007299.

Extensions

a(8) from Brendan McKay, Feb 11 2012