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A178925
Number of n-node simple graphs that are determined by spectrum.
1
1, 2, 4, 11, 32, 146, 934, 10624, 223629, 9444562, 803666188, 134023600111
OFFSET
1,2
LINKS
A. E. Brouwer and E. Spence, Cospectral graphs on 12 vertices, Electr. J. Combin. 16 (2009) N20.
Eric Weisstein's World of Mathematics, Determined by Spectrum
FORMULA
a(n) = A000088(n) - A006608(n).
CROSSREFS
Cf. A000088, A006608 (simple graphs not determined by spectrum).
Sequence in context: A123424 A123449 A123404 * A298445 A294224 A296270
KEYWORD
nonn,hard,more
AUTHOR
Eric W. Weisstein, Dec 29 2010
EXTENSIONS
a(10) from Eric W. Weisstein, Dec 30 2010
a(11)-a(12) from Eric W. Weisstein, Apr 11 2024 (from Brouwer and Spence)
STATUS
approved