Both of these designs featured red lettering with blue or green numbers.

But the comforting blue numbers were still glowing from the clock by her bed, so the power hadn't gone out.

I think it has to do with the density of blue number.

Then somebody handed him a white uniform with 42 in blue numbers on it.

The stamps are two numbers, either red or blue.

Later versions also had blue serial numbers and a small seal moved to the left side of the note.

His wife, Amy, had told him to put on a fresh one, a $1,500 dark blue number.

Pretty sure he came out in a light blue number, which is now jet black.

The two systems are entirely independent; so number 27 blue might be next to number 8 red.

The blue numbers on the microwave said it was now ten minutes before six.