module Seq = let rec cycle xs = seq { yield! xs; yield! cycle xs }

// Tests
let intList = [1..4]
let charList = ['a'..'d']
let objList = [obj (); obj (); obj (); obj ()]

Seq.cycle intList |> Seq.take 20 |> Seq.iter (printfn "%A")
Seq.cycle charList |> Seq.take 20 |> Seq.iter (printfn "%A")
Seq.cycle objList |> Seq.take 20 |> Seq.iter (printfn "%A")