Merge faster Riemann R function #87

Job	Run time
macos_clang (macos-latest, Debug)	5m 28s
linux_gcc (ubuntu-latest, Debug)	4m 38s
macos_clang (macos-latest, Release)	1m 15s
linux_gcc (ubuntu-latest, Release)	2m 37s
linux_clang (ubuntu-latest, Debug)	3m 26s
linux_clang (ubuntu-latest, Release)	1m 10s
linux_gcc_sanitizers	2m 22s
linux_gcc_valgrind	1m 18s
windows_mingw64 (windows-latest, Debug)	5m 16s
windows_msvc2022	2m 27s
windows_mingw64 (windows-latest, Release)	2m 43s
	32m 40s

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