A083547 a(n) = sqrt(sqrt(phi(A083546(n)) * phi(1+A083546(n)))), the 4th root of product of totients of terms and 1+terms of A082788.

1, 12, 24, 36, 36, 60, 60, 72, 80, 96, 120, 120, 120, 144, 144, 168, 180, 240, 264, 360, 360, 432, 480, 504, 480, 480, 720, 720, 720, 720, 840, 840, 864, 840, 840, 840, 840, 960, 900, 960, 960, 1080, 1260, 1224, 1320, 1320, 1440, 1440, 1320, 1440, 1440, 1728

Offset: 1

Author

Labos Elemer, May 21 2003

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..300

Crossrefs

Cf. A000010, A082788, A083538, A083542, A083545, A083546.

Programs

Mathematica

f[x_] := EulerPhi[x]; Do[s=Sqrt[Sqrt[f[n+1]*f[n]]]; If[IntegerQ[s], Print[s]], {n, 1, 1000000}]

Extensions

a(29)-a(52) from Amiram Eldar, Apr 09 2021