1234 is the
natural number
In mathematics, the natural numbers are the numbers 0, 1, 2, 3, and so on, possibly excluding 0. Some start counting with 0, defining the natural numbers as the non-negative integers , while others start with 1, defining them as the positive in ...
following
1233, and preceding 1235. It has two distinct
prime factor
A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways ...
s,
2 and
617
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Year 617 ( DCXVII) was a common year starting on Saturday of the Julian calendar. The denomination 617 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Euro ...
, making it a
squarefree semiprime.
It is the number of
independent vertex sets in a 4×4
square grid
In geometry, the square tiling, square tessellation or square grid is a regular tiling of the Euclidean plane consisting of four squares around every vertex. John Horton Conway called it a quadrille.
Structure and properties
The square tiling ...
, or equivalently, the number of distinct 4×4
binary matrices in which no two adjacent elements are both equal to 1.
A 2012 study of frequently-used
personal identification number
A personal identification number (PIN; sometimes RAS syndrome, redundantly a PIN code or PIN number) is a numeric (sometimes alpha-numeric) passcode used in the process of authenticating a user accessing a system.
The PIN has been the key to faci ...
s (PIN) found that, among 4-digit PIN codes, 1234 is the most frequently chosen.
[ As cited by ]
References
{{Integers, 1000
Integers