A082104 Number of distinct characteristic polynomials among all simple undirected graphs on n nodes.
1, 2, 4, 11, 33, 151, 988, 11453, 247357, 10608128, 901029366, 148187993520
Offset: 1
Links
- Andries E. Brouwer, Numbers of characteristic polynomials and cospectral graphs for A
- A. E. Brouwer and E. Spence, Cospectral graphs on 12 vertices, Electr. J. Combin. 16 (2009) N20. (p. 199).
- Lorentz Jäntschi and Sorana D. Bolboacă, Characteristic Polynomial, Chapter 7, New Frontiers in Nanochemistry, 1st ed., Apple Academic Press, 2020.
- Dan-Marian Joiţa and Lorentz Jäntschi, Extending the Characteristic Polynomial for Characterization of C_20 Fullerene Congeners, Mathematics (2017), 5(4), 84.
- E. Spence, Numbers of characteristic polynomials and cospectral graphs for A
- Eric Weisstein's World of Mathematics, Characteristic Polynomial
Crossrefs
Cf. A000088.
Extensions
One term added by Andries E. Brouwer, Apr 09 2009
Two more terms from Ruperto Corso, Dec 18 2011