  An analysis is conducted of the multipartite entanglement for Gaussian states
generated by the parametric down-conversion of a femtosecond frequency comb.
Using a recently introduced method for constructing optimal entanglement
criteria, a family of tests is formulated for mode decompositions that extends
beyond the traditional bipartition analyses. A numerical optimization over this
family is performed to achieve maximal significance of entanglement
verification. For experimentally prepared 4-, 6-, and 10-mode states, full
entanglement is certified for all of the 14, 202, and 115974 possible
nontrivial partitions, respectively.
