Tool-Assisted Code Golf
Python 2, 69 48 46 44 bytes

print"start\n\n"*19+(27*"A right\n"+"\n")*99


See it in action on youtube!

Automatically found with (a modified version of) this hacky script:

start = 18
oncycle = 21
offcycle = 4


while true do
    emu.poweron()
    -- emu.speedmode("maximum")

    starting = 0
    i = 0
    frames = 0
    last_mario_x = -1

    emu.message(start .. " " .. oncycle .. " ".. offcycle)


    state = 0
    while state ~= 6 and state ~= 11 and frames &lt; 4000 do
        if frames &gt; 500 and frames % 100 == 0 then
            mario_x = memory.readbyte(0x6D) * 0x100 + memory.readbyte(0x86)
            if mario_x == last_mario_x then emu.message("stuck " .. mario_x .. " " .. last_mario_x); break end
            last_mario_x = mario_x
        end

        if starting &lt; start then
            joypad.set(1, {start=1})
            emu.frameadvance(); frames = frames + 1;
            joypad.set(1, {})
            emu.frameadvance(); frames = frames + 1;
            starting = starting + 1
        else
            if i &lt; oncycle then
                joypad.set(1, {A=1, B=1, right=1})
                i = i + 1
            else
                joypad.set(1, {})
                i = i +  1
                if i == oncycle + offcycle then
                    i = 0
                end
            end

            emu.frameadvance()
            frames = frames + 1
        end

        state = memory.readbyte(0x000E)
        if state == 4 then
            emu.message("success!")
            os.exit()
            break
        end

    end

    if start &lt; 30 then
        start = start + 1
    elseif offcycle &lt; 10 then
        start = 18
        offcycle = offcycle + 1
    else
        offcycle = 1
        oncycle = oncycle + 1
    end
end