/usr/include/root/ is in libroot-math-mathmore-dev 5.34.30-0ubuntu8.
This file is owned by root:root, with mode 0o755.
..
/usr/include/root/Math/
/usr/include/root/Math/ChebyshevApprox.h
/usr/include/root/Math/Derivator.h
/usr/include/root/Math/DistFuncMathMore.h
/usr/include/root/Math/GSLFunctionAdapter.h
/usr/include/root/Math/GSLIntegrator.h
/usr/include/root/Math/GSLMCIntegrator.h
/usr/include/root/Math/GSLMinimizer.h
/usr/include/root/Math/GSLMinimizer1D.h
/usr/include/root/Math/GSLMultiRootFinder.h
/usr/include/root/Math/GSLNLSMinimizer.h
/usr/include/root/Math/GSLQuasiRandom.h
/usr/include/root/Math/GSLRndmEngines.h
/usr/include/root/Math/GSLRootFinder.h
/usr/include/root/Math/GSLRootFinderDeriv.h
/usr/include/root/Math/GSLRootHelper.h
/usr/include/root/Math/GSLSimAnMinimizer.h
/usr/include/root/Math/GSLSimAnnealing.h
/usr/include/root/Math/IntegrationTypes.h
/usr/include/root/Math/InterpolationTypes.h
/usr/include/root/Math/Interpolator.h
/usr/include/root/Math/KelvinFunctions.h
/usr/include/root/Math/MCIntegrationTypes.h
/usr/include/root/Math/MCParameters.h
/usr/include/root/Math/MultiNumGradFunction.h
/usr/include/root/Math/MultiRootFinder.h
/usr/include/root/Math/ParamFunction.h
/usr/include/root/Math/PdfFuncMathMore.h
/usr/include/root/Math/Polynomial.h
/usr/include/root/Math/QuantFuncMathMore.h
/usr/include/root/Math/QuasiRandom.h
/usr/include/root/Math/Random.h
/usr/include/root/Math/RootFinderAlgorithms.h
/usr/include/root/Math/SpecFuncMathMore.h
/usr/include/root/Math/Vavilov.h
/usr/include/root/Math/VavilovAccurate.h
/usr/include/root/Math/VavilovAccurateCdf.h
/usr/include/root/Math/VavilovAccuratePdf.h
/usr/include/root/Math/VavilovAccurateQuantile.h
/usr/include/root/Math/VavilovFast.h