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Triangle read by rows: T(n,n) = mobius(n) on the diagonal, zero elsewhere.
21

%I #13 Feb 18 2022 22:15:41

%S 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,

%T 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1

%N Triangle read by rows: T(n,n) = mobius(n) on the diagonal, zero elsewhere.

%C A128407 * [1,2,3,...] = n*mu(n), A055615: (1, -2, -3, 0, -5, 6, -7, 0, ...). A051731 * A128407 = A054524. A128407 * A051731 = A128408.

%H Harvey P. Dale, <a href="/A128407/b128407.txt">Table of n, a(n) for n = 1..1000</a>

%F Infinite lower triangular matrix with mu(n), A008683, as the right border and the rest zeros.

%e First few rows of the triangle:

%e 1;

%e 0, -1;

%e 0, 0, -1;

%e 0, 0, 0, 0;

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

%e 0, 0, 0, 0, 0, 1;

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

%e ...

%t Table[PadLeft[{MoebiusMu[n]},n],{n,10}]//Flatten (* _Harvey P. Dale_, Dec 29 2021 *)

%Y Cf. A051731, A128408, A008683 (row sums and diagonal), A054524.

%K tabl,sign,easy

%O 1,1

%A _Gary W. Adamson_, Mar 01 2007

%E Name improved . - _R. J. Mathar_, Aug 03 2015