login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

A128407
Triangle read by rows: T(n,n) = mobius(n) on the diagonal, zero elsewhere.
21
1, 0, -1, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
OFFSET
1,1
COMMENTS
A128407 * [1,2,3,...] = n*mu(n), A055615: (1, -2, -3, 0, -5, 6, -7, 0, ...). A051731 * A128407 = A054524. A128407 * A051731 = A128408.
LINKS
FORMULA
Infinite lower triangular matrix with mu(n), A008683, as the right border and the rest zeros.
EXAMPLE
First few rows of the triangle:
1;
0, -1;
0, 0, -1;
0, 0, 0, 0;
0, 0, 0, 0, -1;
0, 0, 0, 0, 0, 1;
0, 0, 0, 0, 0, 0, -1;
...
MATHEMATICA
Table[PadLeft[{MoebiusMu[n]}, n], {n, 10}]//Flatten (* Harvey P. Dale, Dec 29 2021 *)
CROSSREFS
Cf. A051731, A128408, A008683 (row sums and diagonal), A054524.
Sequence in context: A074381 A179560 A341602 * A363800 A134286 A023531
KEYWORD
tabl,sign,easy
AUTHOR
Gary W. Adamson, Mar 01 2007
EXTENSIONS
Name improved . - R. J. Mathar, Aug 03 2015
STATUS
approved