1200

Apr 1, 2018 09:28
This is my 1200th post.

Interestingly, this number "1200" has extraordinary properties.

Among natural numbers, only 1200 belongs to both Hamming numbers and Catalan numbers.

Hamming numbers are positive integers whose prime factors are only 2, 3, and 5 (1200 = 2 * 2 * 2 * 2 * 3 * 5 * 5).

Catalan numbers are natural numbers defined as C_n = (2n)!/{(n+1)!n!} (C_8 = 1200).

Incidentally, today is April 1st.

It is true that this is the 1200th post and the number 1200 belongs to Hamming numbers.

However, it is a lie that 1200 belongs to Catalan numbers (actually C_8 is 1430).

As far as I know, 5 is the only number that belongs to both Hamming numbers and Catalan numbers.
1200

今日で1200回目の投稿になります。

実は「1200」という数字は、とても特別な意味を持っています。

「1200」は、自然数の中で唯一、ハミング数でありカタラン数でもあります。

ハミング数とは、どの素因数も5以下の正整数のことです(1200 = 2^4 × 3 × 5^2)。

カタラン数は、C_n = (2n)!/{(n+1)!n!} で表される自然数のクラスです(C_8 = 1200)。

そして、今日は4月1日です。

この記事が1200回目の投稿ということと、1200がハミング数であるということは、本当です。

しかし、1200がカタラン数であるということは、嘘です(C_8 = 1430)。

また、ハミング数かつカタラン数である数は、私の知る限り「5」のみです。
No. 1 artboy598
  • This is my 1200th post.
  • This sentence is perfect! No correction needed!
  • Interestingly, this number "1200" has extraordinary properties.
  • This sentence is perfect! No correction needed!
  • Among natural numbers, only 1200 belongs to both Hamming numbers and Catalan numbers.
  • Among natural numbers, only 1200 belongs to both Hamming numbers and Catalan numbers.
  • Hamming numbers are positive integers whose prime factors are only 2, 3, and 5 (1200 = 2 * 2 * 2 * 2 * 3 * 5 * 5).
  • This sentence is perfect! No correction needed!
  • Catalan numbers are natural numbers defined as C_n = (2n)!/{(n+1)!n!} (C_8 = 1200).
  • This sentence is perfect! No correction needed!
  • Incidentally, today is April 1st.
  • This sentence is perfect! No correction needed!
  • It is true that this is the 1200th post and the number 1200 belongs to Hamming numbers.
  • This sentence is perfect! No correction needed!
  • However, it is a lie that 1200 belongs to Catalan numbers (actually C_8 is 1430).
  • This sentence is perfect! No correction needed!
  • As far as I know, 5 is the only number that belongs to both Hamming numbers and Catalan numbers.
  • This sentence is perfect! No correction needed!

You got me!

Toru
Thank you so much for the correction! (^^)