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A245880 Number of distinct characteristic polynomials among all connected graphs on n nodes. 0
1, 1, 2, 6, 21, 111, 821, 10423, 236064, 10375796 (list; graph; refs; listen; history; text; internal format)
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, 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

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Last modified December 5 17:42 EST 2019. Contains 329768 sequences. (Running on oeis4.)