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A132219
Number of line graphs on n labeled nodes.
1
1, 2, 8, 66, 774, 11885, 230858, 5512821, 157926273, 5323010347, 207833183972, 9280406921629, 468879370270319, 26561064972285450, 1673867356632729422, 116555375609273658636, 8914259769349445083676, 744876885721366948399627
OFFSET
1,2
FORMULA
E.g.f.: exp(x/2-x^3/6)*Sum(A020556(n)*(log(1+x)/2)^n/n!, n=0..infinity).
CROSSREFS
Cf. A132220 (unlabeled case).
Sequence in context: A100623 A231280 A086594 * A226730 A202553 A023164
KEYWORD
nonn
AUTHOR
Vladeta Jovovic, Aug 14 2007
STATUS
approved