login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A143728 Triangle read by rows: termwise product of mu(n) and n-th row of A127368. 1
1, 1, 0, 1, -2, 0, 1, 0, -3, 0, 1, -2, -3, 0, 0, 1, 0, 0, 0, -5, 0, 1, -2, -3, 0, -5, 6, 0, 1, 0, -3, 0, -5, 0, -7, 0, 1, -2, 0, 0, -5, 0, -7, 0, 0, 1, 0, -3, 0, 0, 0, -7, 0, 0, 0, 1, -2, -3, 0, -5, 6, -7, 0, 0, 10, 0, 1, 0, 0, 0, -5, 0, -7, 0, 0, 0, -11, 0, 1, -2, -3, 0, -5, 6, -7, 0, 0, 10, -11, 0, 0 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,5
COMMENTS
The operation A127368 * A128407 forms the termwise product of mu(n) and the n-th row of A127368: deleting all squares and changing the sign of primes to (-1).
Row sums = A143729: (1, 1, -1, -2, -4, -4, -3, -14, ...)
LINKS
FORMULA
Triangle read by rows, A127368 * A128407, 1 <= k <= n; T(n,k) = {1<=k<=n, gcd(k,n)=1} * mu(k).
EXAMPLE
First few terms of the triangle:
1;
1, 0;
1, -2, 0;
1, 0, -3, 0;
1, -2, -3, 0, 0;
1, 0, 0, 0, -5, 0;
1, -2, -3, 0, -5, 6, 0;
1, 0, -3, 0, -5, 0, -7, 0;
...
Example: row 7 = (1, -2, -3, 0, -5, 6, 0). We take row 7 of triangle A127368 which records the relative primes of 7 as (1, 2, 3, 4, 5, 6, 0). Applying the termwise product of the first 7 terms of mu(k): (1, -1, -1, 0, -1, 1, -1), we get (1, -2, -3, 0, -5, 6, 0), noting that the "4" has been deleted.
CROSSREFS
Sequence in context: A175267 A108045 A298972 * A127368 A112552 A048154
KEYWORD
tabl,sign
AUTHOR
Gary W. Adamson, Aug 30 2008
EXTENSIONS
Partially edited by N. J. A. Sloane, Jan 05 2009
a(66) = 0 inserted by Georg Fischer, Jun 05 2023
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 27 16:21 EDT 2024. Contains 373746 sequences. (Running on oeis4.)