Search results
Results from the WOW.Com Content Network
The result must be divisible by 12. 324: 32 × 2 − 4 = 60 = 5 × 12. 13: Form the alternating sum of blocks of three from right to left. The result must be divisible by 13. [7] 2,911,272: 272 − 911 + 2 = −637. Add 4 times the last digit to the rest. The result must be divisible by 13. (Works because 39 is divisible by 13).
Normally, a year is a leap year if it is evenly divisible by four. A year divisible by 100 is not a leap year in the Gregorian calendar unless it is also divisible by 400. For example, 1600 was a leap year, but 1700, 1800 and 1900 were not. Some programs may have relied on the oversimplified rule that "a year divisible by four is a leap year".
Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100, but these centurial years are leap years if they are exactly divisible by 400. For example, the years 1700, 1800, and 1900 are not leap years, but the years 1600 and 2000 are. [8] 1800 calendar, showing that February had only 28 days
In the past 500 years, there was no leap day in 1700, 1800 and 1900, but 2000 had one. In the next 500 years, if the practice is followed, there will be no leap day in 2100, 2200, 2300 and 2500 ...
d() is the number of positive divisors of n, including 1 and n itself; σ() is the sum of the positive divisors of n, including 1 and n itselfs() is the sum of the proper divisors of n, including 1 but not n itself; that is, s(n) = σ(n) − n
A century leap year is a leap year in the Gregorian calendar that is evenly divisible by 400. [1] Like all leap years, it has an extra day in February for a total of 366 days instead of 365. In the obsolete Julian calendar, all years that were divisible by 4, including end-of-century years, were considered leap years. The Julian rule, however ...
Thus, 1/54, in sexagesimal, is 1/60 + 6/60 2 + 40/60 3, also denoted 1:6:40 as Babylonian notational conventions did not specify the power of the starting digit. Conversely 1/4000 = 54/60 3, so division by 1:6:40 = 4000 can be accomplished by instead multiplying by 54 and shifting three sexagesimal places.
A century common year is a common year in the Gregorian calendar that is divisible by 100 but not by 400. Like all common years, these years do not get an extra day in February, meaning they have 365 days instead of 366. These years are the only common years that are divisible by 4.