Английская Википедия:224 (number)

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224 (two hundred [and] twenty-four) is the natural number following 223 and preceding 225.

In mathematics

Шаблон:Infobox number

224 is a practical number,[1] and a sum of two positive cubes Шаблон:Nowrap.[2] It is also Шаблон:Nowrap, making it one of the smallest numbers to be the sum of distinct positive cubes in more than one way.[3]

224 is the smallest k with λ(k) = 24, where λ(k) is the Carmichael function.[4]

The mathematician and philosopher Alex Bellos suggested in 2014 that a candidate for the lowest uninteresting number would be 224 because it was, at the time, "the lowest number not to have its own page on [the English-language version of] Wikipedia".[5]

In other areas

In the SHA-2 family of six cryptographic hash functions, the weakest is SHA-224, named because it produces 224-bit hash values.[6] It was defined in this way so that the number of bits of security it provides (half of its output length, 112 bits) would match the key length of two-key Triple DES.[7]

The ancient Phoenician shekel was a standardized measure of silver, equal to 224 grains, although other forms of the shekel employed in other ancient cultures (including the Babylonians and Hebrews) had different measures.[8] Likely not coincidentally, as far as ancient Burma and Thailand, silver was measured in a unit called a tikal, equal to 224 grains.[9]

See also

References

Шаблон:Reflist

Шаблон:Integers

Шаблон:Num-stub