Did you know that “Sheldon’s theorem” inspired by “The Big Bang Theory” really exists in mathematics?

The Sheldon’s theoremborn from an episode of the sitcom “The Big Bang Theory”, is a fascinating example of how pop culture can influence academia. The basic idea is simple: the protagonist Sheldon Cooper defines the number 73 as the “Chuck Norris of numbers”attributing to it unique properties that subsequently inspired in-depth mathematical investigation.

The number 73, in fact, has several special characteristics. It’s a prime numberi.e. divisible only by 1 and itself, e occupies position number 21 in the list of prime numbers. Reversing its digits, we obtain the number 37, also prime, which occupies position 12 in the same list.

Curiously, 12 is the inverse of 21. Furthermore, the product of the digits of 73 (7 × 3) is precisely 21, its position in the sequence of prime numbers. Finally, in binary representation, 73 becomes 1001001, one palindromic sequence.

The mathematical theorem of Christopher Spicer and Carl Pomerance

Fascinated by these properties, mathematicians Christopher Spicer And Carl Pomerance have studied the problem, rigorously defining the concept of “Sheldon’s prime number”. A number with this qualification must satisfy two conditions: the product of its digits must coincide with its position in the list of prime numbers, and by inverting its digits another prime number must be obtained, whose position respects the same mirror criterion.

After years of work, the two have proven that 73 is the only prime number to possess both propertiestransforming the so-called “Sheldon Conjecture” into a mathematical theorem published in the journal American Mathematical Monthly.

The peculiarity of this result lies not so much in its practical importance, but in its symbolic and didactic value. The episode demonstrates how humor and stories from popular culture can stimulate interest in complex disciplines like mathematics. Spicer himself stated that this theorem is an excellent example of recreational mathematicsuseful for introducing students to academic topics through a fun approach.