[votan]

Confirmed.

Try to change

local function combinations(lst, n)
    local a, number, select, newlist
    newlist = {}
    number = #lst
    select = n
    a = {}
    for i = 1, select do
        a[#a + 1] = i
    end

    while (1) do
        local newrow = {}
        for i = 1, select do
            newrow[#newrow + 1] = lst[a[i]]
        end
        newlist[#newlist + 1] = newrow
        local i = select
        while (a[i] == (number - select + i)) do
            i = i - 1
        end
        if (i < 1) then break end
        a[i] = a[i] + 1
        for j = i, select do
            a[j] = a[i] + j - i
        end
    end
    return newlist
end