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A140981
Number of graphs with n vertices that have an even determinant for the adjacency matrix.
2
1, 1, 4, 7, 34, 109, 1044, 8303, 274668, 7451736, 1018997864
OFFSET
1,3
FORMULA
a(n) = A000088(n) - A141040(n/2) for n even, a(n) = A000088(n) for n odd.
CROSSREFS
KEYWORD
more,nonn
AUTHOR
Tanya Khovanova, Aug 18 2008
EXTENSIONS
a(8)-a(10) from Andrew Howroyd, Nov 04 2017
a(11) from A000088 added by Max Alekseyev, Feb 20 2024
STATUS
approved