2
1

for (i in 1:nrow(plan)) {
  paste0("day_1_", i) <- permutations(3, 3, v = names(plan)[which(plan[i,] == 1, arr.ind=T)[, "col"]])
}

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    2

    1

    library(gtools)
    
    list_df <- list()
    for (i in 1:nrow(plan)) {
       list_df[[i]] <- data.frame(permutations(3, 3, 
               v = names(plan)[which(plan[i,] == 1, arr.ind=T)[, "col"]]))
    }
    

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    0

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