## What Wikipedia taught me about 42

### By Kamila Shamsie

It exists already in law: There are 42 laws of cricket. Law 42 covers fair and unfair play.

It exits also in the realm of terror: In Japanese 4 (shi) and 2 (ni) are together pronounced like “going to death.” Because of that, in Japan, 42 is considered as a disastrous number. This happens in Hong Kong too, as 42 sounds like “easy death” in Cantonese.

If you're going for ‘can you believe someone really proposed that’, it’s been done: In 1965, mathematician Paul Cooper theorized that the fastest, most efficient way to travel across continents would be to bore a straight hollow tube directly through the earth, evacuate it (remove the air), and then just fall through. The first half of the journey consists of free-fall acceleration, while the second half consists of an exactly equal deceleration. The time for such a journey works out to be 42 minutes. Remarkably, even if the tube does not pass through the exact center of the earth, the time for a journey powered entirely by gravity always works out to be 42 minutes, as long as the tube remains friction-free.

Perplexing? Beat this: It is a Catalan number. Consequently 42 is the number of non-crossing partitions of a set of five elements; the number of triangulations of a heptagon; the number of rooted ordered binary trees with six leaves; the number of ways in which five pairs of nested parentheses can be arranged; etc.

Transformative?: The first book to be printed with movable type, the famous Gutenberg Bible, is also known as the ‘42-line Bible’, after the number of lines of print on each page.

All in all, 42 is weighed down enough as it is. Leave it alone now, let us remember it as Douglas Adam’s answer to Life, The Universe and Everything, or the angle in degrees for which a rainbow appears.