D_UL

D_U

D_UR

a₁

a₂

a₃

0

0

1

√

√

0

1

0

1

0

0

√

√

0

1

1

√

1

0

1

√

1

1

0

√

0

1

2

√

√

1

0

2

√

√

1

2

0

√

√

0

1

3

√

√

1

0

3

√

√

1

3

0

√

√

0

2

1

√

√

2

0

1

√

√

2

1

0

√

√

0

3

1

√

√

3

0

1

√

√

3

1

0

√

√

1

1

2

√

1

2

1

√

2

1

1

√

1

2

2

√

√

2

1

2

√

√

2

2

1

√

√

1

1

3

√

1

3

1

√