let indices = Seq.unfold (fun x -> Some(x, x + 1)) 0
let zipWithIndex coll = Seq.zip coll indices
printfn "%A" ([12; 8; 9; 90; 3; 24] |> zipWithIndex |> Seq.minBy fst)
bGV0IGluZGljZXMgPSBTZXEudW5mb2xkIChmdW4geCAtPiBTb21lKHgsIHggKyAxKSkgMApsZXQgemlwV2l0aEluZGV4IGNvbGwgPSBTZXEuemlwIGNvbGwgaW5kaWNlcwoKcHJpbnRmbiAiJUEiIChbMTI7IDg7IDk7IDkwOyAzOyAyNF0gfD4gemlwV2l0aEluZGV4IHw+IFNlcS5taW5CeSBmc3Qp