A245880 Number of distinct characteristic polynomials among all connected graphs on n nodes.

1, 1, 2, 6, 21, 111, 821, 10423, 236064, 10375796

Offset

1,3

Links

Table of n, a(n) for n=1..10.

Travis Hoppe and Anna Petrone, Encyclopedia of Finite Graphs

T. Hoppe and A. Petrone, Integer sequence discovery from small graphs, arXiv preprint arXiv:1408.3644 [math.CO], 2014.

T. Hoppe and A. Petrone, Integer sequence discovery from small graphs, Discr. Appl. Math. 201 (2016) 172-181.

Eric Weisstein's World of Mathematics, Characteristic Polynomial

Crossrefs

Cf. A082104 (simple graphs, including disconnected ones, with unique characteristic polynomials).

Sequence in context: A156808 A245882 A267653 * A076324 A303032 A076325

Adjacent sequences: A245877 A245878 A245879 * A245881 A245882 A245883

Keyword

nonn,hard,more

Author

Travis Hoppe and Anna Petrone, Aug 05 2014

Extensions

Terms corrected by Eric M. Schmidt, Mar 20 2015

Status

approved