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A272658 Number of distinct characteristic polynomials of n X n matrices with elements {-1, 0, +1}. 11
3, 16, 209, 8739, 1839102 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

REFERENCES

Robert M. Corless, Bohemian Eigenvalues, Talk Presented at Computational Discovery in Mathematics (ACMES 2), University of Western Ontario, May 12 2016. (Talk based on joint work with Steven E. Thornton, Sonia Gupta, Jonathan Brino-Tarasoff, Venkat Balasubramanian.)

LINKS

Table of n, a(n) for n=1..5.

Eunice Y. S. Chan, Algebraic Companions and Linearizations, The University of Western Ontario (Canada, 2019) Electronic Thesis and Dissertation Repository. 6414.

Eunice Y. S. Chan, Robert Corless, A new kind of companion matrix, Electronic Journal of Linear Algebra, Volume 32, Article 25, 2017, see p. 335.

Robert M. Corless et al., Bohemian Eigenvalues.

CROSSREFS

Six classes of matrices mentioned in Rob Corless's talk: this sequence, A272659, A272660, A272661, A272662, A272663.

Other properties of this class of matrices: A271570, A271587, A271588. - Steven E. Thornton, Jul 13 2016

Sequence in context: A166860 A196562 A317073 * A326903 A113597 A000273

Adjacent sequences:  A272655 A272656 A272657 * A272659 A272660 A272661

KEYWORD

nonn,more,hard

AUTHOR

N. J. A. Sloane, May 15 2016

EXTENSIONS

a(4) found by Daniel Lichtblau, May 13 2016

a(5) found by Daniel Lichtblau and Steven E. Thornton, May 19 2016

STATUS

approved

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Last modified November 26 19:27 EST 2020. Contains 338641 sequences. (Running on oeis4.)