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The first evidence for the decay B+→π+e+e- is reported using proton-proton collision data recorded by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb-1. A signal excess with a significance of 3.2σ is observed and the branching fraction is measured to be B(B+→π+e+e-)=(2.4-0.8+0.9 -0.2+0.4)×10-8, where the first set of uncertainties is statistical and the second is systematic. The result is consistent with the Standard Model expectation.