The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.



Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS").
Other ways to donate

(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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)



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.)


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.


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




N. J. A. Sloane, May 15 2016


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

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



Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

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