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A106480
Row sums of inverse of sequence array for Euler phi function.
4
1, 0, -1, 0, -1, 2, -1, -2, 5, -4, 1, 0, -7, 18, -9, -12, 17, -24, 31, 6, -67, 94, -49, -60, 157, -230, 217, 118, -619, 758, -461, -252, 1509, -2490, 1867, 780, -4531, 6932, -5543, -820, 11885, -21248, 17591, 2586, -32415, 58070, -54325, -56
OFFSET
0,6
FORMULA
G.f.: 1/(Sum_{j>=0} phi(j+1)*x^j*(1-x)).
MATHEMATICA
T[n_, k_] := If[k <= n, EulerPhi[n - k + 1], 0]; With[{max = 48}, Tinv = Inverse[Table[T[n, k], {n, 0, max - 1}, {k, 0, max - 1}]]; Total[Transpose[Table[Tinv[[n, k]], {n, 1, max}, {k, 1, max}]]]] (* Amiram Eldar, Nov 16 2024 *)
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Paul Barry, May 03 2005
STATUS
approved