Henry Dudeney, a master puzzle-maker posed this challenge. Suppose you had a block of eight postage stamps connected together in two rows of four stamps. Number the stamps 1-4 on the first row and 5-6 on the second. Dudeney stated that there are forty different ways to fold them up so that the first stamp is on top facing upward and the other stamps are below it. For example, if you fold the block in half along the horizontal line, then fold them accordion-style, the stamp number 1 is on top and the rest are below it in the following order: 5, 6, 2, 3, 7, 8, 4.
The puzzle: fold the block of stamps in the order 1, 5, 6, 4, 8, 7, 3, 2. For a more difficult challenge try 1, 3, 7, 5, 6, 8, 4, 2. The block of stamps must remain intact: you cannot cut, tear, spindle, or mutilate.