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

1,2

Links

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

Mathematica

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

Crossrefs

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

Sequence in context: A098113 A172415 A195556 * A009185 A102308 A354583

Adjacent sequences: A083544 A083545 A083546 * A083548 A083549 A083550

Keyword

nonn

Author

Labos Elemer, May 21 2003

Extensions

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

Status

approved