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

%I #14 Jun 05 2023 07:06:31

%S 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,

%T -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,

%U -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

%N Triangle read by rows: termwise product of mu(n) and n-th row of A127368.

%C 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).

%C Row sums = A143729: (1, 1, -1, -2, -4, -4, -3, -14, ...)

%F Triangle read by rows, A127368 * A128407, 1 <= k <= n; T(n,k) = {1<=k<=n, gcd(k,n)=1} * mu(k).

%e First few terms of the triangle:

%e 1;

%e 1, 0;

%e 1, -2, 0;

%e 1, 0, -3, 0;

%e 1, -2, -3, 0, 0;

%e 1, 0, 0, 0, -5, 0;

%e 1, -2, -3, 0, -5, 6, 0;

%e 1, 0, -3, 0, -5, 0, -7, 0;

%e ...

%e 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.

%Y Cf. A008683, A127368, A128407.

%K tabl,sign

%O 1,5

%A _Gary W. Adamson_, Aug 30 2008

%E Partially edited by _N. J. A. Sloane_, Jan 05 2009

%E a(66) = 0 inserted by _Georg Fischer_, Jun 05 2023

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 April 24 10:11 EDT 2024. Contains 371935 sequences. (Running on oeis4.)