On a theorem of Conant-Vogtmann (Q812521)

\textit{M. Kontsevich} [Formal (non) commutative symplectic geometry, Boston: Birkhäuser (1993; Zbl 0821.58018)] introduced a super vector space of certain finite oriented graphs; this is called the graph complex. \textit{J. Conant} and \textit{K. Vogtmann} [Math. Ann. 327, 545--573 (2003; Zbl 1092.17014)] produced a new differential, Lie bracket and Lie cobracket on this graph complex, yielding a Lie bialgebra structure on the subspace of one-particle irreducible graphs. The author shows the whole graph complex to be a strong homotopy Lie super bialgebra in the sense of his paper [Math. Res. Lett. 10, 109--124 (2003; Zbl 1103.18010)].