cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A369700 Möbius transform of reduced totient function (A002322).

Original entry on oeis.org

1, 0, 1, 1, 3, 0, 5, 0, 4, 0, 9, -1, 11, 0, -1, 2, 15, 0, 17, -1, -1, 0, 21, 0, 16, 0, 12, -1, 27, 0, 29, 4, -1, 0, 3, 0, 35, 0, -1, 0, 39, 0, 41, -1, 4, 0, 45, 0, 36, 0, -1, -1, 51, 0, 7, 0, -1, 0, 57, 1, 59, 0, -4, 8, -3, 0, 65, -1, -1, 0
Offset: 1

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Author

Miles Englezou, Jan 29 2024

Keywords

Comments

Since A002322(n) = A000010(n) for n = 1, 2, 4, and odd prime powers, a(n) = A007431(n) for the same values of n.

Examples

			a(8) = mu(1)*lambda(8) + mu(2)*lambda(4) + mu(4)*lambda(2) + mu(8)*lambda(1) = 0.
		

Crossrefs

Programs

  • Mathematica
    a[n_] := DivisorSum[n, MoebiusMu[#] * CarmichaelLambda[n/#] &]; Array[a, 100] (* Amiram Eldar, Jan 29 2024 *)
  • PARI
    a(n) = sumdiv(n, d, moebius(d)*lcm(znstar(n/d)[2]))

Formula

a(n) = Sum_{d|n} A008683(d) * A002322(n/d).