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# User:Alonso del Arte

Here is one of my projects: IMSLP Orchestra to do world premiere recording of Symphony by Franz Asplmayr.

I graduated from Wayne State University with a bachelor's degree in Film Studies in 2008. In 2004, I wrote for WSU's student newspaper, The South End, an article on the celebration for the 100,000th sequence to be added to the OEIS, A100000.

## Sequence of the Day for May 24

A164102: Decimal expansion of
 2 π 2
.
19.739208802...
A lot of us have quite enough trouble with just three dimensions. The hypersurface “area” of a unit hypersphere in four dimensions (i.e. a 3-sphere) is
 2 π 2 (length unit) 3
. The “volume” of the contained hyperball (i.e. a 4-ball) is
 π 2 2
(length unit) 4
. Compare it with the 3-dimensional unit ball: the surface area of a unit sphere in three dimensions (i.e. a 2-sphere) is
 4 π (length unit) 2
. The volume of the contained ball (i.e. a 3-ball) is
 4 π 3
(length unit) 3
. The “volume” of the
 n
-dimensional unit hyperball is given by
Vn (1) =
 2 ⌈ n / 2⌉ π ⌊ n / 2⌋ n!!
(length unit)n, n ≥ 0,
where
 n!!
is the double factorial. (For
 n = 0
, we get a 0-dimensional “volume” of
 1 (length unit) 0
, i.e. the pure number 1, result of the empty product.) For a recursion relation, see: The Volume of a Hypersphere.

• A239797 Decimal expansion of ${\displaystyle {\frac {\sqrt {3}}{\sqrt[{3}]{4}}}}$.
• A238271 Decimal expansion of ${\displaystyle \sum _{n=1}^{\infty }{\frac {\mu (n)}{3^{n}}}}$.
• A237042 UPC check digits.
• A236603 Lowest canonical Gray cycles of length ${\displaystyle 2n}$.
• A235365 Smallest odd prime factor of ${\displaystyle 3^{n}+1}$.
• A234522 Decimal expansion of ${\displaystyle {\sqrt[{4}]{7}}-{\sqrt[{4}]{5}}}$.
• A233748 Number of graphs on n vertices with edges colored with at most four interchangeable colors under the symmetries of the full edge permutation group.
• A232499 Number of unit squares, aligned with a Cartesian grid, completely within the first quadrant of a circle centered at the origin ordered by increasing radius.
• A231963 Concatenate ${\displaystyle n}$ with its UPC check digit.
• A230624 Numbers ${\displaystyle n}$ with property that for every base ${\displaystyle b\geq 2}$, there is a number ${\displaystyle m}$ such that ${\displaystyle m+s(m)=n}$, where ${\displaystyle s(m)}$ is the sum of digits in the base ${\displaystyle b}$ expansion of ${\displaystyle m}$.

## Sequences in the News

• Feb 01 2018 Alphabet announced a $8,589,869,056 =$A000396(6) stock buyback.
• Jan 03 2018 Largest known term of A000043 announced: 77232917.
• Nov 18 2016 PrimeGrid proves that 10223 is not a Sierpinski number, since 10223 × 2 31172165 + 1 is prime. So no changes to A076336 for now.
• Sep 14 2016 Tom Greer discovers the twin primes 2996863034895 × 2 1290000 ± 1 using PrimeGrid, TwinGen and LLR.
• Jan 19 2016 Largest known term of A000043 announced: 274207281, also discovered by Curtis Cooper.
• Mar 02 2014 Fredrik Johansson announces a computation of the partition number p(10 20) ≈ 1.8381765 × 10 11140086259, the largest known term of A000041.
• Dec 06 2013 Microsoft launches a challenge to find large non-Mersenne primes, A138837.