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URL: https://oeis.org/A077027

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A077027
Number of simple integral graphs on n nodes.
3
1, 2, 3, 6, 10, 20, 33, 71, 121, 269, 492
OFFSET
1,2
COMMENTS
Generated at the suggestion of Ed Pegg Jr.
LINKS
Eric Weisstein's World of Mathematics, Integral Graph
FORMULA
Euler transform of A064731. - Eric M. Schmidt, Mar 23 2015
a(n) = A287154(n) + A064731(n).
CROSSREFS
Cf. A064731 (number of simple connected integral graphs).
Cf. A287154 (number of simple disconnected integral graphs).
Cf. A363065 (number of Laplacian integral graphs).
Sequence in context: A214002 A305889 A135452 * A030436 A030227 A180272
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, Oct 18 2002
EXTENSIONS
a(1) corrected and a(10)-a(11) added (using A064731) by Eric M. Schmidt, Mar 23 2015
STATUS
approved