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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

Sequence of the Day for October 14

A008619:
1 +
 n 2
, n   ≥   0.
(Positive integers repeated twice.)
{ 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, ... }
Smallest positive integer whose harmonic mean with another positive integer is
 n
. For example,
 a (6) = 4
is already given (as 4 is the smallest positive integer such that the harmonic mean of 4 (with 12) is 6) —but the harmonic mean of 2 (with  −  6) is also 6 and 2 < 4, so the two positive integer restrictions need to be imposed to rule out both 2 and  −  6. Note also that this sequence is the second outermost diagonal of Lozanić’s triangle.

• A239797 Decimal expansion of ${\frac {\sqrt {3}}{\sqrt[{3}]{4}}}$ .
• A238271 Decimal expansion of $\sum _{n=1}^{\infty }{\frac {\mu (n)}{3^{n}}}$ .
• A237042 UPC check digits.
• A236603 Lowest canonical Gray cycles of length $2n$ .
• A235365 Smallest odd prime factor of $3^{n}+1$ .
• A234522 Decimal expansion of ${\sqrt[{4}]{7}}-{\sqrt[{4}]{5}}$ .
• 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 $n$ with its UPC check digit.
• A230624 Numbers $n$ with property that for every base $b\geq 2$ , there is a number $m$ such that $m+s(m)=n$ , where $s(m)$ is the sum of digits in the base $b$ expansion of $m$ .

Sequences in the News

• Dec 25 2018 German Heise-News "integers, please" column explains A003173 and OEIS.
• 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: 74207281, also discovered by Curtis Cooper.