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A353213
Number of simple unlabeled non-null graphs on <= n nodes.
1
1, 3, 7, 18, 52, 208, 1252, 13598, 288266, 12293434, 1031291298, 166122463890, 50668153831842, 29104823811067330, 31455590793615376098, 64032471295321173271026, 245999896624828253856990802, 1787823725042236528801735181650, 24639597076850046760911809226614418, 645514762392876691902925550299969363858
OFFSET
1,2
COMMENTS
Also the number of (non-null) graph minors of the complete graph K_n.
LINKS
Eric Weisstein's World of Mathematics, Graph Minor
Eric Weisstein's World of Mathematics, Simple Graph
FORMULA
a(n) = A006897(n) - 1.
a(n) = Sum_{k=1..n} A000088(k).
CROSSREFS
Cf. A000088 (number of simple graphs on n nodes).
Cf. A006897 (number of simple graphs on 0 to n nodes).
Sequence in context: A180166 A369842 A256873 * A276906 A062416 A366578
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Apr 30 2022
STATUS
approved