Are these defective Nanos?

I wrote some code that sent out a repeated pulse on the Nano A6 pin. My Oscope failed to show the pulse. I tried the same pulse on pin 7, and there it was. So I grabbed another Nano, and tried the same. Same result.

void setup() 
{

  pinMode(7, OUTPUT);
  pinMode(A6, OUTPUT);

}

void loop() 
{
    digitalWrite(A6, LOW);
    delay(50);
    digitalWrite(A6, HIGH);

    digitalWrite(7, LOW);
    delay(50);
    digitalWrite(7, HIGH);

    delay(1000);

}

I believe all pins on a Nano should serve as digital pins. Anybody else ever had this problem?

The Nano has 8 analog inputs, each of which provide 10 bits of resolution (i.e. 1024 different values). By default they measure from ground to 5 volts, though is it possible to change the upper end of their range using the analogReference() function. Analog pins 6 and 7 cannot be used as digital pins. Additionally, some pins have specialized functionality:

oops.

A6 and A7 are analog inputs only. All documentation and pinout pics I've seen make this quite clear.

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