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A054645
Triangle T(n,k) of asymmetric n X n binary matrices with k=0..n^2 ones under action of dihedral group of the square D_4.
0
0, 0, 2, 6, 10, 10, 6, 2, 0, 0, 0, 1, 10, 63, 207, 525, 954, 1395, 1550, 1395, 954, 525, 207, 63, 10, 1, 0, 0, 1, 28, 258, 1503, 6475, 21810, 59540, 134333, 254178, 407040, 555356, 648054, 648054, 555356, 407040, 254178, 134333, 59540, 21810, 6475
OFFSET
3,3
COMMENTS
Row sums give A054385.
EXAMPLE
The batch [0,0,2,6,10,10,6,2,0,0] gives the numbers of asymmetric 3 X 3 binary matrices with k=0..9 ones under action of dihedral group of the square D_4.
There are 6 nonequivalent asymmetric 3 X 3 binary matrices with 3 ones under action of D_4:
[0 0 0] [0 0 0] [0 0 0] [0 0 0] [0 0 0] [0 0 1]
[0 0 1] [0 0 1] [0 1 0] [0 1 1] [1 0 1] [0 0 0]
[1 0 1] [1 1 0] [0 1 1] [1 0 0] [0 0 1] [1 1 0].
CROSSREFS
Cf. A054252.
Sequence in context: A141257 A122882 A136700 * A337645 A225271 A357725
KEYWORD
nonn,tabf,nice
AUTHOR
Vladeta Jovovic, May 15 2000
STATUS
approved