%I #31 Oct 14 2023 14:05:54
%S 1,-1,1,-2,0,2,-1,-1,0,2,-4,0,0,0,4,2,-2,-2,0,0,2,-6,0,0,0,0,0,6,-1,
%T -1,0,-2,0,0,0,4,-2,0,-4,0,0,0,0,0,6,4,-4,0,0,-4,0,0,0,0,4,-10,0,0,0,
%U 0,0,0,0,0,0,10,2,2,-2,-4,0,-2,0,0,0,0,0,4
%N Triangle read by rows: T(n,k) = A023900(n/k)*phi(k) if k divides n, T(n,k) = 0 otherwise (n >= 1, 1 <= k <= n).
%C Sum_{k=1..n} T(n,k) = A063524(n).
%F T(n,k) = A023900(n/k)*phi(k) if k divides n, T(n,k) = 0 otherwise (n >= 1, 1 <= k <= n).
%e {
%e {1}, = 1
%e {-1, 1}, = 0
%e {-2, 0, 2}, = 0
%e {-1, -1, 0, 2}, = 0
%e {-4, 0, 0, 0, 4}, = 0
%e {2, -2, -2, 0, 0, 2}, = 0
%e {-6, 0, 0, 0, 0, 0, 6}, = 0
%e {-1, -1, 0, -2, 0, 0, 0, 4}, = 0
%e {-2, 0, -4, 0, 0, 0, 0, 0, 6}, = 0
%e {4, -4, 0, 0, -4, 0, 0, 0, 0, 4}, = 0
%e {-10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 10}, = 0
%e {2, 2, -2, -4, 0, -2, 0, 0, 0, 0, 0, 4} = 0
%e }
%t nn = 12; g[n_] := DivisorSum[n, MoebiusMu[#] # &]; Flatten[Table[Table[If[Mod[n, k] == 0, g[n/k]*EulerPhi[k], 0], {k, 1, n}], {n, 1, nn}]]
%Y Cf. A000010, A023900, A366444, A054524, A054525, A063524, A054522, A054523, A129691, A127649.
%K sign,tabl
%O 1,4
%A _Mats Granvik_, Oct 12 2023