%%qsharp

open Microsoft.Quantum.Canon;
open Microsoft.Quantum.Intrinsic;
open Microsoft.Quantum.Convert;

operation GetSequence() : Int[]
{
    mutable sequence = [];

    // let sequence = new int[6];
    mutable count = 0;
    let start = 1;
    let end = 5;

    repeat {
        count++;

        sequence[count] = 2^(count + 1) - 1;
    } until count > end;

    return sequence;
}