Question: How to return or get a list-variable back from a function or code in Maple 2021?

I want to use this L3 list as the index of another list. I am trying to create a model for short time electricity load forecasting in Maple. I am fairly new to maple coding structures. Can anybody suggest an easier way for doing this kind of thing in Maple? Can I use matrix generation? Please give me suggestions. 
Note: Currently working in a Doc File. 
The code is pasted below: 

L1 := [seq([seq(seq1[i], i = 1 .. 7)], i = 1 .. 24)];

L2 := [seq(i, i = 1 .. 24)];

local(i, j, L3);
L3 = [];
for i to 24 do
    for j to 7 do if i = 1 then L3[i][j] := L1[i][j]; else L3[i][j] := L1[i][j] + L2[i] - 1; end if; end do;
end do;
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