A search for the Bc meson decaying into the channels J/ψπ+ and J/ψl+vl (l = e or μ) is performed in a sample of 3.9 million hadronic Z decays collected by the ALEPH detector. This search results in the observation of 0 and 2 candidates in each of these channels, respectively, while 0.44 and 0.81 background events are expected. The following 90% confidence level upper limits are derived:<!- FORMULA OMITTED -> Another B+c -> J/ψ(e+e-)μ+vμ candidate with very low background probability, found in an independent analysis, is also described in detail.
