Today, January 11th 2016, I'm 24389 days old and what's special is that this number is 29 cubed or 29 x 29 x 29. Days like this are rare. For example, 283 or 21592 occurred on May 10th 2009 and 303 or 27000 will occur on March 6th 2023. Cubes of prime numbers are even rarer of course. The prime preceding 29 is 23 and 233 or 12167 occurred on July 26th 1982. The prime following 29 is 31 and 313 or 29791 will occur on October 26th 2030 when I'm 81 years of age (if I make it that far).
24389 has a surprisingly large number of entries in the Online Encyclopaedia of Integer Sequences (OEIS), 174 in fact which is unusual for a composite number of this magnitude. The first entry is for OEIS A000578: the cubes a(n)=n3. The sequence, up to 24389 when n=29, looks like this:
0, 1, 8, 27, 64, 125, 216, 343, 512, 729, 1000, 1331, 1728, 2197, 2744, 3375, 4096, 4913, 5832, 6859, 8000, 9261, 10648, 12167, 13824, 15625, 17576, 19683, 21952, 24389
The next entry is OEIS A030078: cubes of primes. The sequence, up to 24389, is: 8, 27, 125, 343, 1331, 2197, 4913, 6859, 12167, 24389.
From WolframAlpha, we find that 24389 is also a cube that is expressible as the sum of two squares in two different ways:
24389=582+1452=652+1422
Additionally, we find that 24389 is the hypotenuse of a primitive Pythagorean triple:
243892=159392+184602. So, all in all, an interesting number.
24389 has a surprisingly large number of entries in the Online Encyclopaedia of Integer Sequences (OEIS), 174 in fact which is unusual for a composite number of this magnitude. The first entry is for OEIS A000578: the cubes a(n)=n3. The sequence, up to 24389 when n=29, looks like this:
0, 1, 8, 27, 64, 125, 216, 343, 512, 729, 1000, 1331, 1728, 2197, 2744, 3375, 4096, 4913, 5832, 6859, 8000, 9261, 10648, 12167, 13824, 15625, 17576, 19683, 21952, 24389
The next entry is OEIS A030078: cubes of primes. The sequence, up to 24389, is: 8, 27, 125, 343, 1331, 2197, 4913, 6859, 12167, 24389.
From WolframAlpha, we find that 24389 is also a cube that is expressible as the sum of two squares in two different ways:
24389=582+1452=652+1422
Additionally, we find that 24389 is the hypotenuse of a primitive Pythagorean triple:
243892=159392+184602. So, all in all, an interesting number.
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