Most idiomatic way to write batchesOf size seq in F#

Question

I\'m trying to learn F# by rewriting some C# algorithms I have into idiomatic F#.

One of the first functions I\'m trying to rewrite is a batchesOf where:

Answer 1

This can be done without recursion if you want

[0..20] 
    |> Seq.mapi (fun i elem -> (i/size),elem) 
    |> Seq.groupBy (fun (a,_) -> a)
    |> Seq.map (fun (_,se) -> se |> Seq.map (snd));;
val it : seq> =
  seq
    [seq [0; 1; 2; 3; ...]; seq [5; 6; 7; 8; ...]; seq [10; 11; 12; 13; ...];
     seq [15; 16; 17; 18; ...]; ...]

Depending on how you think this may be easier to understand. Tomas' solution is probably more idiomatic F# though