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A091471
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Number of n X n matrices with entries {-1,1} that are diagonalizable over the complex numbers.
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2
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OFFSET
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1,1
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COMMENTS
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See A091472 for definition of diagonalizable and for Mathematica definitions.
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LINKS
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MATHEMATICA
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Table[Count[Matrices[n, {-1, 1}], _?DiagonalizableQ], {n, 4}]
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PROG
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(Sage)
import itertools
def a(n):
ans, W = 0, itertools.product([-1, 1], repeat=n*n)
for w in W:
if Matrix(QQbar, n, n, w).is_diagonalizable(): ans += 1
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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