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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 an 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 AUTHOR Simone Severini, Apr 28 2004 STATUS approved

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Last modified August 6 11:14 EDT 2020. Contains 336246 sequences. (Running on oeis4.)