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A091471 Number of n X n matrices with entries {-1,1} that are diagonalizable over the complex numbers. 2
2, 12, 464, 50224, 25095232 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
See A091472 for definition of diagonalizable and for Mathematica definitions.
LINKS
Eric Weisstein's World of Mathematics, Diagonalizable Matrix
MATHEMATICA
Table[Count[Matrices[n, {-1, 1}], _?DiagonalizableQ], {n, 4}]
PROG
(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
return ans # Robin Visser, Sep 27 2023
CROSSREFS
Sequence in context: A350790 A296623 A009510 * A357895 A012625 A012630
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, Jan 12 2004
EXTENSIONS
a(5) from Robin Visser, Sep 27 2023
STATUS
approved

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Last modified March 19 03:18 EDT 2024. Contains 370952 sequences. (Running on oeis4.)