A093378 - OEIS

A093378

a(n) = numerator of any non-diagonal entry of the matrix A^n, where A is described in the Comments lines.

2, 12, 22, 168, 1558, 5148, 8062, 177072, 860882, 738492, 121008888, 298775878, 1232566932, 14864798542, 58374617952

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OFFSET

1,1

COMMENTS

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

LINKS

CROSSREFS

KEYWORD

nonn,frac,more

AUTHOR

STATUS

approved