/usr/include/boost/multiprecision/ is in libboost1.62-dev 1.62.0+dfsg-5.
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/usr/include/boost/multiprecision/concepts/
/usr/include/boost/multiprecision/concepts/mp_number_archetypes.hpp
/usr/include/boost/multiprecision/cpp_bin_float/
/usr/include/boost/multiprecision/cpp_bin_float.hpp
/usr/include/boost/multiprecision/cpp_bin_float/io.hpp
/usr/include/boost/multiprecision/cpp_bin_float/transcendental.hpp
/usr/include/boost/multiprecision/cpp_dec_float.hpp
/usr/include/boost/multiprecision/cpp_int/
/usr/include/boost/multiprecision/cpp_int.hpp
/usr/include/boost/multiprecision/cpp_int/add.hpp
/usr/include/boost/multiprecision/cpp_int/bitwise.hpp
/usr/include/boost/multiprecision/cpp_int/checked.hpp
/usr/include/boost/multiprecision/cpp_int/comparison.hpp
/usr/include/boost/multiprecision/cpp_int/cpp_int_config.hpp
/usr/include/boost/multiprecision/cpp_int/divide.hpp
/usr/include/boost/multiprecision/cpp_int/import_export.hpp
/usr/include/boost/multiprecision/cpp_int/limits.hpp
/usr/include/boost/multiprecision/cpp_int/literals.hpp
/usr/include/boost/multiprecision/cpp_int/misc.hpp
/usr/include/boost/multiprecision/cpp_int/multiply.hpp
/usr/include/boost/multiprecision/cpp_int/serialize.hpp
/usr/include/boost/multiprecision/cpp_int/value_pack.hpp
/usr/include/boost/multiprecision/debug_adaptor.hpp
/usr/include/boost/multiprecision/detail/
/usr/include/boost/multiprecision/detail/big_lanczos.hpp
/usr/include/boost/multiprecision/detail/bitscan.hpp
/usr/include/boost/multiprecision/detail/default_ops.hpp
/usr/include/boost/multiprecision/detail/digits.hpp
/usr/include/boost/multiprecision/detail/dynamic_array.hpp
/usr/include/boost/multiprecision/detail/et_ops.hpp
/usr/include/boost/multiprecision/detail/float_string_cvt.hpp
/usr/include/boost/multiprecision/detail/functions/
/usr/include/boost/multiprecision/detail/functions/constants.hpp
/usr/include/boost/multiprecision/detail/functions/pow.hpp
/usr/include/boost/multiprecision/detail/functions/trig.hpp
/usr/include/boost/multiprecision/detail/generic_interconvert.hpp
/usr/include/boost/multiprecision/detail/integer_ops.hpp
/usr/include/boost/multiprecision/detail/min_max.hpp
/usr/include/boost/multiprecision/detail/no_et_ops.hpp
/usr/include/boost/multiprecision/detail/number_base.hpp
/usr/include/boost/multiprecision/detail/number_compare.hpp
/usr/include/boost/multiprecision/detail/rebind.hpp
/usr/include/boost/multiprecision/detail/ublas_interop.hpp
/usr/include/boost/multiprecision/detail/utype_helper.hpp
/usr/include/boost/multiprecision/float128.hpp
/usr/include/boost/multiprecision/gmp.hpp
/usr/include/boost/multiprecision/integer.hpp
/usr/include/boost/multiprecision/logged_adaptor.hpp
/usr/include/boost/multiprecision/miller_rabin.hpp
/usr/include/boost/multiprecision/mpfi.hpp
/usr/include/boost/multiprecision/mpfr.hpp
/usr/include/boost/multiprecision/number.hpp
/usr/include/boost/multiprecision/random.hpp
/usr/include/boost/multiprecision/rational_adaptor.hpp
/usr/include/boost/multiprecision/tommath.hpp
/usr/include/boost/multiprecision/traits/
/usr/include/boost/multiprecision/traits/explicit_conversion.hpp
/usr/include/boost/multiprecision/traits/extract_exponent_type.hpp
/usr/include/boost/multiprecision/traits/is_backend.hpp
/usr/include/boost/multiprecision/traits/is_byte_container.hpp
/usr/include/boost/multiprecision/traits/is_restricted_conversion.hpp