A077219 Floor(geometric mean of the reduced residue system modulo n).

1, 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 7, 8, 9, 8, 9, 9, 10, 10, 11, 11, 12, 12, 12, 12, 12, 13, 14, 14, 14, 14, 15, 15, 16, 16, 16, 16, 17, 17, 18, 18, 18, 19, 20, 19, 20, 20, 20, 21, 22, 22, 23, 22, 23, 23, 23, 24, 25, 25, 25, 25, 26, 26, 27, 27, 27, 27, 28, 28

Offset

1,5

Comments

1. The reduced residue system modulo n is the set of integers k between 1 and n which are coprime to n. The geometric mean of the positive integers a_1,...,a_n is the n-th root of a_1*...*a_n. 2. The arithmetic mean of the reduced residue system modulo n is A065033.

Links

Table of n, a(n) for n=1..78.

Mathematica

gm[l_] := Module[{k, p}, k = Length[l]; p = Product[l[[i]], {i, 1, k}]; p^(1/k)]; rp[n_] := Module[{a, i}, a = {1}; For[i = 2, i < n, i++, If[GCD[i, n] == 1, a = Append[a, i]]]; a];

Crossrefs

Sequence in context: A192262 A026414 A353090 * A026405 A226033 A054404

Adjacent sequences: A077216 A077217 A077218 * A077220 A077221 A077222

Keyword

nonn

Author

Joseph L. Pe, Nov 30 2002

Status

approved