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We report a preliminary branching fraction of
(1.80+/- 0.37 stat +/- 0.23 syst)x 10^{-4}
for the charmless exclusive semileptonic B+ -> pi^0 l+ nu decay,
where l can be either a muon or an electron. This
result is based on data corresponding to an integrated luminosity of
81fb^-1 collected at the Upsilon(4S) resonance with the
BaBar detector. The analysis uses BBbar events that are tagged by a
B meson reconstructed in the semileptonic B- -> D^0 l- nubar (X) decays,
where X can be either a gamma or a pi^0 from a D^{*} decay.
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