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 A093378 a(n) = numerator of any non-diagonal entry of the matrix A^n, where A is described in the Comments lines. 1
 2, 12, 22, 168, 1558, 5148, 8062, 177072, 860882, 738492, 121008888, 298775878, 1232566932, 14864798542, 58374617952 (list; graph; refs; listen; history; text; internal format)
 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 Cf. A066771. Sequence in context: A073211 A233137 A094626 * A012664 A012545 A009514 Adjacent sequences: A093375 A093376 A093377 * A093379 A093380 A093381 KEYWORD nonn,frac,more AUTHOR Simone Severini, Apr 28 2004 STATUS approved

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Last modified March 23 23:09 EDT 2023. Contains 361454 sequences. (Running on oeis4.)