

A006608


Number of nnode graphs not determined by their spectrum.
(Formerly M1981)


4



0, 0, 0, 0, 2, 10, 110, 1722, 51039, 2560606, 215331676, 31067572481
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,5


REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).


LINKS



CROSSREFS



KEYWORD

nonn,hard,more


AUTHOR



EXTENSIONS



STATUS

approved



