The first stamp lists the numbers of the Fibonacci sequence: 1, 2, 3, 5, 8, 13, 21, etc. in alternating bold letters.
The second stamp shows the ratios of each successive pair: 2:1, 3:2, 5:3, 8:5, 13:8, 21:13, etc. in alternating bold letters
The third stamp shows the golden ratio (1.6180339887… ).
The ratios of the Fibonacci pairs converge on as the series increases. Curiously, the decimal representation of Phi (Φ)
on this stamp has two errors. 3653 should be 36563, and 0911 should be 0917.