Folding a Strip of Labeled Stamps

​
folding
1
stamps
2
This Demonstration illustrates the different ways a strip of stamps labeled 1 through
n
can be folded into a stack one stamp wide. In each figure, the colored lines represent the stamps and the dotted lines represent the perforation between adjacent stamps.

Details

​
Snapshot 1: for 1, 2, and 3 stamps, the number of labeled stamp foldings is equal to the number of permutations of
n
items, or
n!
Snapshots 2, 3: for
n>3
stamps, the number of labeled stamp foldings is less than
n!
, since some permutations lead to impossible foldings; for example,
{1,3,2,4}
is an impossible folding, since the perforation joining stamps 1 and 2 would intersect with the perforation joining 3 and 4
M. Gardner, "The Combinatorics of Paper Folding," Wheels, Life and Other Mathematical Amusements, New York: W. H. Freeman, 1983 pp. 60–61.

External Links

Stamp Folding (Wolfram MathWorld)

Permanent Citation

Robert Dickau
​
​"Folding a Strip of Labeled Stamps"​
​http://demonstrations.wolfram.com/FoldingAStripOfLabeledStamps/​
​Wolfram Demonstrations Project​
​Published: March 24, 2011