A241584 - OEIS

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A241584

Number of orbits of Sym(n)^2 under action of Iso_1(n).

2

1, 4, 11, 43, 155, 761, 4043, 27190

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..8.

Mathieu Bogaerts and Peter Dukes, Semidefinite programming for permutation codes, Discrete Math. 326 (2014), 34--43. MR3188985.

FORMULA

Proposition 3.2 of Bogaerts et al. gives an explicit formula.

CROSSREFS

Cf. A241585, A110143.

Sequence in context: A163133 A176574 A323792 * A176576 A110143 A149279

Adjacent sequences: A241581 A241582 A241583 * A241585 A241586 A241587

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, May 12 2014

STATUS

approved