  Searches for resonant and nonresonant pair-produced Higgs bosons (HH)
decaying respectively into ll nu nu, through either W or Z bosons, and bbbar
are presented. The analyses are based on a sample of proton-proton collisions
at sqrt(s) = 13 TeV, collected by the CMS experiment at the LHC, corresponding
to an integrated luminosity of 35.9 inverse femtobarns. Data and predictions
from the standard model are in agreement within uncertainties. For the standard
model HH hypothesis, the data exclude at 95% confidence level a product of the
production cross section and branching fraction larger than 72 fb,
corresponding to 79 times the prediction, consistent with expectations.
Constraints are placed on different scenarios considering anomalous couplings,
which could affect the rate and kinematics of HH production. Upper limits at
95% confidence level are set on the production cross section of narrow-width
spin-0 and spin-2 particles decaying to Higgs boson pairs, the latter produced
with minimal gravity-like coupling.
