R Under development (unstable) (2025-12-21 r89216 ucrt) -- "Unsuffered Consequences"
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Platform: x86_64-w64-mingw32/x64

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> # Force single-threaded execution for unit tests
> Sys.setenv(
+   OMP_NUM_THREADS = "1",
+   OMP_THREAD_LIMIT = "",
+   KMP_DEVICE_THREAD_LIMIT = "",
+   KMP_ALL_THREADS = "",
+   KMP_TEAMS_THREAD_LIMIT = "",
+   OPENBLAS_NUM_THREADS = "1",
+   MKL_NUM_THREADS = "1",
+   VECLIB_MAXIMUM_THREADS = "1"
+ )
> 
> proc.time()
   user  system elapsed 
   0.10    0.03    0.12