1,1

A =

[ -(3/5)-(2/5)i,-(2/5)i,-(2/5)i,-(2/5)i ]

[ -(2/5)i,-(3/5)+(2/5)i,-(2/5)i,(2/5)i ]

[ -(2/5)i,-(2/5)i,-(3/5)+(2/5)i,(2/5)i ]

[ -(2/5)i,(2/5)i,(2/5)i,-(3/5)-(2/5)i ]

is the Cayley transform of the matrix iH, where H =

[1,1,1,1]

[1,-1,1,-1]

[1,1,-1,-1]

[1,-1,-1,1]

is an Hadamard matrix of order 4 and i is the imaginary unit.

Table of n, a(n) for n=1..15.

Cf. A066771.

Sequence in context: A073211 A233137 A094626 * A012664 A012545 A009514

Adjacent sequences: A093375 A093376 A093377 * A093379 A093380 A093381

nonn,frac

Simone Severini, Apr 28 2004

approved