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A048616 Denominator of mass (Sum 1/|Aut(H)|) of Hadamard matrices of order 4n. 5
192, 21504, 190080, 573440, 218880, 40480, 2106, 53329920 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
V. Alvarez, J. A. Armario, M. D. Frau and F. Gudiel, The maximal determinant of cocyclic (-1, 1)-matrices over D_{2t}, Linear Algebra and its Applications, 2011.
EXAMPLE
1/192, 1/21504, 1/190080, 27/573440, 127/218880, 34603/40480, 278617/2106, 264156210586399/53329920, ...
CROSSREFS
Sequence in context: A205760 A338532 A035833 * A206707 A199007 A199006
KEYWORD
frac,nonn,hard,nice
AUTHOR
N. J. A. Sloane, E. M. Rains
EXTENSIONS
a(8) from Brendan McKay, Feb 11 2012
STATUS
approved

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Last modified April 16 13:51 EDT 2024. Contains 371725 sequences. (Running on oeis4.)