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A218855 Imaginary part of the arithmetic derivative for the triangle of Gaussian integers z = r + i*I, with r >= 0 and i >= 0. 4

%I #4 Nov 09 2012 15:32:43

%S 0,0,0,-2,0,2,0,0,0,1,-8,-2,0,2,8,-3,0,0,0,0,3,-6,-3,-2,1,2,3,8,0,0,0,

%T -2,2,0,0,1,-24,-5,-8,-2,0,2,8,5,24,0,-4,0,1,0,0,2,0,4,6,-16,-5,-6,-3,

%U -2,0,2,3,6,5,16,0,0,-3,0,-3,0,0,3,0,3,0,1

%N Imaginary part of the arithmetic derivative for the triangle of Gaussian integers z = r + i*I, with r >= 0 and i >= 0.

%C The real part is in A218854. Consult A099379 for the arithmetic derivative of Gaussian integers.

%H T. D. Noe, <a href="/A218855/b218855.txt">Rows n = 0..100 of triangle, flattened</a>

%e Triangle:

%e 0

%e 0, 0

%e -2, 0, 2

%e 0, 0, 0, 1

%e -8, -2, 0, 2, 8

%e -3, 0, 0, 0, 0, 3

%e -6, -3, -2, 1, 2, 3, 8

%e 0, 0, 0, -2, 2, 0, 0, 1

%t di[0]=0; di[1]=0; di[ -1]=0; di[I]=0; di[ -I]=0; di[n_] := Module[{f, unt}, f=FactorInteger[n, GaussianIntegers->True]; unt=(Abs[f[[1, 1]]]==1); If[unt, f=Delete[f, 1]]; f=Transpose[f]; Plus@@(n*f[[2]]/f[[1]])]; Im[Table[di[n-i + I*i], {n, 0, 12}, {i, 0, n}]]

%Y Cf. A099379, A099380.

%K sign,tabl

%O 0,4

%A _T. D. Noe_, Nov 09 2012

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Last modified August 31 17:39 EDT 2024. Contains 375572 sequences. (Running on oeis4.)