A078580 Moebius function mu of the average of n-th twin prime pair.

0, 1, 0, 0, -1, -1, 0, 0, -1, 0, -1, 0, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 1, 0, 1, 0, -1, -1, 0, 0, -1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, -1, 1, 0, 0, -1, 0, 0, 0, 0, -1, 0, 0, 1, 0, -1, 0, -1, 0, -1, 0, 0, -1, 0, 0, -1, 0, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, -1, 0, 0, 0, 0, 0

Offset: 1

Author

Reinhard Zumkeller, Nov 29 2002

Keywords

• sign

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A008683, A014574, A078579.

Programs

Mathematica

midQ[n_] := PrimeQ[n-1] && PrimeQ[n+1]; MoebiusMu[Select[Range[4000], midQ]] (* Amiram Eldar, Nov 03 2019 *)

Formula

a(n) = A008683(A014574(n)).