A search for the production of Higgs boson pairs in proton–proton collisions at a centre-of-mass energy of
13 TeV is presented, using a data sample corresponding to an integrated luminosity of 35.9 fb¯¹ collected
with the CMS detector at the LHC. Events with one Higgs boson decaying into two bottom quarks
and the other decaying into two τ leptons are explored to investigate both resonant and nonresonant
production mechanisms. The data are found to be consistent, within uncertainties, with the standard
model background predictions. For resonant production, upper limits at the 95% confidence level are
set on the production cross section for Higgs boson pairs as a function of the hypothesized resonance
mass and are interpreted in the context of the minimal supersymmetric standard model. For nonresonant
production, upper limits on the production cross section constrain the parameter space for anomalous
Higgs boson couplings. The observed (expected) upper limit at 95% confidence level corresponds to about
30 (25) times the prediction of the standard model.