A125093 - OEIS

%I #6 Aug 12 2015 20:59:31

%S 1,-2,2,-3,0,3,0,-4,0,4,-5,0,0,0,5,6,-6,-6,0,0,6,-7,0,0,0,0,0,7,0,0,0,

%T -8,0,0,0,8,0,0,-9,0,0,0,0,0,9,10,-10,0,0,-10,0,0,0,0,10,-11,0,0,0,0,

%U 0,0,0,0,0,11,0,12,0,-12,0,-12,0,0,0,0,0,12,-13,0,0,0,0,0,0,0,0,0,0,0,13,14,-14,0,0,0,0,-14,0,0,0,0,0,0,14,15,0,-15,0

%N Triangle T(n,k) = n*A054525(n,k) read by rows.

%F T(n,1) = n*mu(n) = A055615(n).

%e First few rows of the triangle are:

%e 1;

%e -2, 2;

%e -3, 0, 3;

%e 0, -4, 0, 4;

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

%e 6, -6, -6, 0, 0, 6;

%e -7, 0, 0, 0, 0, 0, 7;

%e ...

%p A125093 := proc(n,k) if n = k then n; elif n mod k = 0 then n*numtheory[mobius](n/k) ; else 0; end if; end proc:

%p seq(seq(A125093(n,k),k=1..n),n=1..16) ; # _R. J. Mathar_, Apr 10 2011

%Y Cf. A055615, A051731, A127648.

%K tabl,easy,sign

%O 1,2

%A _Gary W. Adamson_, Jan 22 2007

%E Offset and definition corrected by _R. J. Mathar_, Apr 10 2011