Epsilon: Unable to make a recurrent sequence of the first term U_1

[BriacLP]

Today, in mathematics an exercise gave us the sequence defined on U_n+1= (n*Un+4)/ (n+1) and the first term U_1=1.
Unfortunately, it is impossible to put U_1 in the first term and only U_0, which means that the whole sequence is wrong (we get all the time 4 except for U_0=1)

[boricj]

Adding a "First term" setting on the sequence options screen is probably a good way to fix this.

[Ecco]

Oh, interesting! Thanks @BriacLP for reporting this!

[ian-abbott]

So, replace the initial "U₀" and "U₁" terms with "U_a" and "U_a+1", and add a setting for "a" as the initial value for "n"?

[BriacLP]

So, replace the initial "U0" and "U1" terms with "Ua" and "Ua+1", and add a setting for "a" as the initial value for "n"?

Why not directly allow to choose between U_0, U_1 etc...?

[ian-abbott]

Why not directly allow to choose between U_0, U_1 etc...?

Having an "a" setting would let you choose to start the sequence at U₀, or U₁, or U₂, etc.

So for your example sequence, you could set "U_n+1 = (n * U_n + 4) / (n + 1)", "a = 1", and "U_a = 1".

[BriacLP]

I find it less easy (even if I understand how to do it) than directly being able to choose by clicking on "U_0" another first term. I saw this as if when we clicked on U_n and the computation proposes U_n, U_n+1 or U_n+2.

[artaxxx]

Fixed by #289